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Cornell University
1.
Perez Cordoba, Xavier.
Life-Cycle Cost Optimization For Foundation Engineering.
Degree: PhD, Civil and Environmental Engineering, 2013, Cornell University
URL: http://hdl.handle.net/1813/34381
► The use of reliability-based design (RBD) in foundation engineering offers several advantages over traditional methods. Uncertainties in the load and capacity terms of the design…
(more)
▼ The use of reliability-based design (RBD) in foundation engineering offers several advantages over traditional methods. Uncertainties in the load and capacity terms of the design equations can be evaluated rationally using probability theory, and the resultant probability of failure is a comprehensible measure of risk for non-technical people. However, there are a few drawbacks that have not been addressed effectively so far. For example, it is necessary to select target safety levels, typically from the reliability implied in traditional design methods. Also, the resulting reliability is a nominal value that can be significantly different from the true reliability derived from observed failure rates. This issue is rarely mentioned in the literature, but it affects the utility of probability as a communication tool. In addition, costs are not considered explicitly in the design process, and calculations can be excessively complex and timeconsuming for simple projects. A new framework to determine optimum foundation designs that result in minimum life-cycle costs is presented herein. The traditional approach for design
optimization is to minimize an objective function, such as the sum of initial costs and expected cost of failure. Existing
optimization methods require a number of initial assumptions and use nominal probabilities of failure, leading to inaccurate results. In the proposed framework, the true probability of failure is estimated using Monte Carlo simulation (MCS) or the first order reliability method (FORM). This process considers the variability of input parameters and the probability of "human errors". Although optimum design parameters can be obtained with the proposed framework, it would not be used in practice often, because it requires knowledge of reliability methods. A simplified approach is necessary to avoid complex calculations and facilitate its widespread use in ordinary projects. Therefore, a simplified method for approximate economic
optimization is proposed. In an effort to close the gap between research and practice in foundation engineering, all the calculations shown herein can be reproduced in a simple spreadsheet with nonlinear
optimization capabilities.
Advisors/Committee Members: Kulhawy, Fred Howard (coChair), Bisogni Jr, James John (coChair), Grigoriu, Mircea Dan (committee member), Stewart, Harry Eaton (committee member).
Subjects/Keywords: foundation engineerining; structural optimization; reliability
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APA (6th Edition):
Perez Cordoba, X. (2013). Life-Cycle Cost Optimization For Foundation Engineering. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/34381
Chicago Manual of Style (16th Edition):
Perez Cordoba, Xavier. “Life-Cycle Cost Optimization For Foundation Engineering.” 2013. Doctoral Dissertation, Cornell University. Accessed March 07, 2021.
http://hdl.handle.net/1813/34381.
MLA Handbook (7th Edition):
Perez Cordoba, Xavier. “Life-Cycle Cost Optimization For Foundation Engineering.” 2013. Web. 07 Mar 2021.
Vancouver:
Perez Cordoba X. Life-Cycle Cost Optimization For Foundation Engineering. [Internet] [Doctoral dissertation]. Cornell University; 2013. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/1813/34381.
Council of Science Editors:
Perez Cordoba X. Life-Cycle Cost Optimization For Foundation Engineering. [Doctoral Dissertation]. Cornell University; 2013. Available from: http://hdl.handle.net/1813/34381

University of Ontario Institute of Technology
2.
Cook, Adam George Mount.
Front underride protection devices: design methodology for heavy vehicle crashworthiness.
Degree: 2016, University of Ontario Institute of Technology
URL: http://hdl.handle.net/10155/644
► North American Heavy Vehicles contribute to a third of all road fatalities in Canada. Head on collisions are one of the most severe, as the…
(more)
▼ North American Heavy Vehicles contribute to a third of all road fatalities in Canada. Head on collisions are one of the most severe, as the mismatch of vehicle weight and sizing intensifies when a passenger vehicle is impacted. To improve crash safety, Front Underride Protection Devices (FUPDs) are a proposed solution to establishing a compatible collision between a passenger vehicle and a heavy vehicle. The European Union is among numerous administrations to regulate FUPDs, yet FUPDs are nonexistent in North America. Current regulations conform to European Cab-over Engine Tractors designs. Implementation of current regulations in North American conflicts with the widely driven Conventional Style Tractor due to the different design space for a FUPDs. This study builds on developing regulations for North America, and establishes a design methodology to developing and optimizing FUPDs for the Conventional Style Tractor enlightening the crashworthy importance of front underride protection devices to improving road safety. Advanced two stage
optimization methodology was outlined to ensure industry targets are embedded with in the design to develop lightweight and cost effective devices. Recommendations for the modifications of the ECE R93 for Conventional Style Tractor are outlined; P1 load magnitudes requirements for FUPD stiffness should be increased from the regulated 80 kN to 160 kN to improve small overlap collisions. Regulated geometric parameters were recommended to have a minimal frontal contact height of 240mm, with ground clearance set between 350mm to 400mm. Geometric configurations were outlined and restricted to conform to the aerodynamic curvatures of the tractors bumper. After validation of the
National Crash Analysis Center (NCAC) Toyota Yaris finite element analysis (FEA) model for side impact, the addition of a FUPD enhanced the survivability of passenger vehicle. The work achieved in enhancing the design methodology for industrial implementation and outlining regulations for North America.
Advisors/Committee Members: El-Gindy, Moustafa.
Subjects/Keywords: Crashworthiness; FEA; Design; Structural; Optimization
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APA (6th Edition):
Cook, A. G. M. (2016). Front underride protection devices: design methodology for heavy vehicle crashworthiness. (Thesis). University of Ontario Institute of Technology. Retrieved from http://hdl.handle.net/10155/644
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Cook, Adam George Mount. “Front underride protection devices: design methodology for heavy vehicle crashworthiness.” 2016. Thesis, University of Ontario Institute of Technology. Accessed March 07, 2021.
http://hdl.handle.net/10155/644.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Cook, Adam George Mount. “Front underride protection devices: design methodology for heavy vehicle crashworthiness.” 2016. Web. 07 Mar 2021.
Vancouver:
Cook AGM. Front underride protection devices: design methodology for heavy vehicle crashworthiness. [Internet] [Thesis]. University of Ontario Institute of Technology; 2016. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/10155/644.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Cook AGM. Front underride protection devices: design methodology for heavy vehicle crashworthiness. [Thesis]. University of Ontario Institute of Technology; 2016. Available from: http://hdl.handle.net/10155/644
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Victoria
3.
Sedaghati, Ramin.
Investigations in structural optimization of nonlinear problems using the finite element method.
Degree: Department of Mechanical Engineering, 2018, University of Victoria
URL: https://dspace.library.uvic.ca//handle/1828/9120
► Structural optimization is an important field in engineering with a strong foundation on continuum mechanics, structural finite element analysis, computational techniques and optimization methods. Research…
(more)
▼ Structural optimization is an important field in engineering with a strong foundation on continuum mechanics,
structural finite element analysis, computational techniques and
optimization methods. Research in
structural optimization of linear and geometrically nonlinear problems using the force method has not received appropriate attention by the research community.
The present thesis constitutes a comprehensive study in the area of
structural optimization. Development of new methodologies for analysis and
optimization and their integration in finite element computer programs for analysis and design of linear and nonlinear
structural problems are among the most important contributions.
For linear problems, a force method formulation based on the complementary energy is proposed. Using this formulation, the element forces are obtained without the direct generation of the compatibility matrix. Application of the proposed method in
structural size
optimization under stress, displacement and frequency constraints has been investigated and its efficiency is compared with the conventional displacement formulation. Moreover, an efficient methodology based on the integrated force method is developed for topology
optimization of adaptive structures under static and dynamic loads. It has been demonstrated that
structural optimization based on the force method is computationally more efficient.
For nonlinear problems, an efficient methodology has been developed for
structural optimization of geometrical nonlinear problems under system stability constraints. The technique combines the nonlinear finite element method based on the displacement control technique for analysis and optimality criterion methods for
optimization. Application of the proposed methodology has been investigated for shallow structures. The efficiency of the proposed
optimization algorithms are compared with the mathematical programming method based on the Sequential Quadratic Programming technique. It is shown that
structural design
optimization based on the linear analysis for structures with intrinsic geometric nonlinearites may lead to
structural failure.
Finally, application of the group theoretic approach in
structural optimization of geometrical nonlinear symmetric structures under system stability constraint has been investigated. It has been demonstrated that
structural optimization of nonlinear symmetric structures using the group theoretic approach is computationally efficient and excellent agreement exists between the full space and the reduced subspace optimal solutions.
Advisors/Committee Members: Tabarrok, Bez (supervisor), Suleman, Afzal (supervisor), Dost, Sadik (supervisor).
Subjects/Keywords: Structural optimization; Nonlinear functional analysis
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sedaghati, R. (2018). Investigations in structural optimization of nonlinear problems using the finite element method. (Thesis). University of Victoria. Retrieved from https://dspace.library.uvic.ca//handle/1828/9120
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sedaghati, Ramin. “Investigations in structural optimization of nonlinear problems using the finite element method.” 2018. Thesis, University of Victoria. Accessed March 07, 2021.
https://dspace.library.uvic.ca//handle/1828/9120.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sedaghati, Ramin. “Investigations in structural optimization of nonlinear problems using the finite element method.” 2018. Web. 07 Mar 2021.
Vancouver:
Sedaghati R. Investigations in structural optimization of nonlinear problems using the finite element method. [Internet] [Thesis]. University of Victoria; 2018. [cited 2021 Mar 07].
Available from: https://dspace.library.uvic.ca//handle/1828/9120.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sedaghati R. Investigations in structural optimization of nonlinear problems using the finite element method. [Thesis]. University of Victoria; 2018. Available from: https://dspace.library.uvic.ca//handle/1828/9120
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Montana State University
4.
Condori Quispe, Hugo Orlando.
Implementation of null steering algorithms in a compact analog array.
Degree: MS, College of Engineering, 2014, Montana State University
URL: https://scholarworks.montana.edu/xmlui/handle/1/3344
► In this thesis, the implementation of null steering algorithms in a compact analog array is demonstrated and validated. The performance of the null steering algorithms…
(more)
▼ In this thesis, the implementation of null steering algorithms in a compact analog array is demonstrated and validated. The performance of the null steering algorithms is validated through extensive simulation and hardware implementation. The results of the techniques of null steering, including controlling the complex weights, usually have to rely on simulations to study system performances, design trade-offs, and system
optimization, which by itself can be quite complex and a time-consuming task. Even after extensive simulations, it is not easy to get insights as to what parameters determine system performance in different system parameters, and the interactions on system parameters. Therefore, experimentation and deployment on a real system is required. Few studies have proposed null steering algorithms studies using real implementations. With this motivation, this work presents comprehensive performance comparison of some of the available null steering techniques using an analog array. The contributions of this thesis are: optimize the performance of null steering algorithms taking into account realistic considerations in the simulations and demonstrating the benefits through extensive simulations; and verify the performance of the null steering system through experimental implementation using a simple, compact, lightweight, low cost, high gain, high throughput analog antenna array.
Advisors/Committee Members: Chairperson, Graduate Committee: Richard Wolff (advisor).
Subjects/Keywords: Algorithms.; Antenna arrays.; Mathematical optimization.; Structural optimization.
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Condori Quispe, H. O. (2014). Implementation of null steering algorithms in a compact analog array. (Masters Thesis). Montana State University. Retrieved from https://scholarworks.montana.edu/xmlui/handle/1/3344
Chicago Manual of Style (16th Edition):
Condori Quispe, Hugo Orlando. “Implementation of null steering algorithms in a compact analog array.” 2014. Masters Thesis, Montana State University. Accessed March 07, 2021.
https://scholarworks.montana.edu/xmlui/handle/1/3344.
MLA Handbook (7th Edition):
Condori Quispe, Hugo Orlando. “Implementation of null steering algorithms in a compact analog array.” 2014. Web. 07 Mar 2021.
Vancouver:
Condori Quispe HO. Implementation of null steering algorithms in a compact analog array. [Internet] [Masters thesis]. Montana State University; 2014. [cited 2021 Mar 07].
Available from: https://scholarworks.montana.edu/xmlui/handle/1/3344.
Council of Science Editors:
Condori Quispe HO. Implementation of null steering algorithms in a compact analog array. [Masters Thesis]. Montana State University; 2014. Available from: https://scholarworks.montana.edu/xmlui/handle/1/3344
5.
Muller, Theodorus Ernst.
A comparison of structural optimization techniques with extension towards multi-objective problems.
Degree: MEng, Civil Engineering, 2017, Stellenbosch University
URL: http://hdl.handle.net/10019.1/102719
► ENGLISH ABSTRACT: Structural optimization is becoming an integral part of the modern structural design process in the search to yield more economical structures. The optimization…
(more)
▼ ENGLISH ABSTRACT: Structural optimization is becoming an integral part of the modern
structural design process in the search to yield more economical structures. The optimization of structures is typically performed with the objective to minimize weight or displacement primarily for cost reasons.
Normally only one objective is considered, but methods enabling the consideration of multiple objectives have been developed. With respect to truss and frame structures, there are three well-known aspects which
can be considered during the optimization process, namely, member sizing, shape and topology. These aspects refer to the size of the
structure's members, the internal member configuration and its nodal positioning respectively. During the optimization, these aspects can be considered individually, simultaneously or sequentially, although typically only member size is considered due to its simplicity. This study aims to quantify the weight reduction in the resulting truss structure by
applying a more complex optimization approach such as considering the three aspects simultaneously. Furthermore, this study also aims to determine whether or not a meaningful weight reduction can be achieved
by adjusting the prescribed deflection limit of a frame structure whose maximum deflection can be regarded as non-critical, for example a rural warehouse.
These aims are achieved by researching both general and structural
optimization as well as available algorithms for successfully optimizing a structure. Software is developed to find solutions to both single- and multi-objective optimization problems. The software is used to optimize various truss problems found in literature by considering different combinations of the aforementioned structural aspects. The software is also used to optimize a selection of frame structures in a multi-objective It is concluded that a 22% more economical solution can be found by
considering the three aspects simultaneously as opposed to considering only member size. From the frame structures considered in this study, it is concluded that the majority of the structure's weight can be reduced before the deflection limit is reached. Therefore, an increase in the displacement limit is not required.
AFRIKAANSE OPSOMMING: Strukturele optimering vorm 'n belangrike deel van die moderne struktuurontwerp proses om ten einde meer ekonomiese strukture te
verkry. Strukture word tipies geoptimeer met die doel om die betrokke struktuur se gewig of verplasing te minimeer. Alhoewel metodes ontwikkel
is vir die oorweging van meer as een doel, word normaalweg slegs een
oorweeg. Ten opsigte van vakwerk en raam strukture is daar drie aspekte wat oorweeg kan word tydens die optimeringsproses, naamlik
elementgrootte, vorm en topologie. Hierdie aspekte verwys respektiewelik
na die grootte van elemente, die interne element konfigurasie en die posisionering van knooppunte. Tydens die optimeringsproses kan hierdie aspekte individueel, gelyktydig of agtereenvolgend oorweeg word, alhoewel meestal slegs die…
Advisors/Committee Members: Van der Klashorst, Etienne, Van Rooyen, G. C., Stellenbosch University. Faculty of Engineering. Dept. of Civil Engineering..
Subjects/Keywords: Truss structures; UCTD; Structural optimization; Genetic algorithms; Combinatorial optimization; Structural frames
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Muller, T. E. (2017). A comparison of structural optimization techniques with extension towards multi-objective problems. (Thesis). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/102719
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Muller, Theodorus Ernst. “A comparison of structural optimization techniques with extension towards multi-objective problems.” 2017. Thesis, Stellenbosch University. Accessed March 07, 2021.
http://hdl.handle.net/10019.1/102719.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Muller, Theodorus Ernst. “A comparison of structural optimization techniques with extension towards multi-objective problems.” 2017. Web. 07 Mar 2021.
Vancouver:
Muller TE. A comparison of structural optimization techniques with extension towards multi-objective problems. [Internet] [Thesis]. Stellenbosch University; 2017. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/10019.1/102719.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Muller TE. A comparison of structural optimization techniques with extension towards multi-objective problems. [Thesis]. Stellenbosch University; 2017. Available from: http://hdl.handle.net/10019.1/102719
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology
6.
De Marco, Andrea (author).
Application of Evolutionary Structural Optimization to Reinforced Concrete Structures.
Degree: 2018, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:efd1ad24-017f-48ac-8e31-184339a9d148
► The present thesis has the objective to create a procedure for the automatic preliminary design of reinforced concrete structures, based on the Evolutionary Structural Optimization…
(more)
▼ The present thesis has the objective to create a procedure for the automatic preliminary design of reinforced concrete structures, based on the Evolutionary
Structural Optimization method (ESO). The developed algorithm performs heuristic topology
optimization based on multiple criteria, in subsequent
optimization cycles executed in series. In each ESO cycle, it is possible to perform material addition, removal or transition between a couple of materials, i.e. steel, concrete and void. Each
optimization cycle is governed by an optimality criterion chosen from: stiffness, Von Mises, Drucker-Prager, tension stress criteria or linear interpolation of previous ones. The finite element analysis used in the algorithm regards all materials as linear elastic. The reaching of maximum strength and failure of materials is not taken into account. The automated design process of reinforced concrete structures has been separated in two problems: the form-finding of reinforced concrete structure as a whole and the definition of internal distribution between steel and concrete. The first problem is solved, in the first
optimization cycle, with a ``standard'' ESO procedure, with the only difference in choosing a Von Mises
optimization criterion over a ``classical'' stiffness criterion. The second problem is solved, in the second and third
optimization cycles, combining in series two additional ``modified'' ESO procedures and introducing gradual transition in
optimization criteria through linear interpolation of sensitivity numbers. The combined criteria for the second cycle are a Von Mises and Drucker-Prager
optimization criteria, while for the third cycle, a Drucker-Prager and tensile stress
optimization criteria. Moreover, additional geometrical constraints are applied, to ensure a set minimal distance between steel and outer boundaries, i.e. concrete cover, and to ensure optimal angle preservation for steel members found during
optimization, introducing two new ``density'' matrices called \emph{cover} and \emph{mask}. Summarizing, the preliminary design of reinforced concrete structures is dealt with three cycles of ESO
optimization procedures executed in series, with
optimization criteria that gradually change with continuity between the different cycles over the whole process. The developed procedure has been tested on several case studies, both from ESO and reinforced concrete literature. The defined ESO process has been found to generate solutions with steel correctly placed in tensile stress zones both to resist bending and shear. Generally, the presence of remaining tensile stresses in concrete zones in the solutions is absent or very limited, and in latter cases their magnitude is very small compared to other stresses. Obtained solutions cannot be directly used as such for reinforcement layouts definition but, in combination with principal stresses plots and engineering judgement, they are able to suggest useful resulting reinforcement layouts. As result of the specificities introduced for…
Advisors/Committee Members: Hendriks, Max (mentor), Rots, Jan (graduation committee), Braam, Rene (graduation committee), Langelaar, Matthijs (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Evolutionary Structural Optimization; Bi-directional Evolutionary Structural Optimization; Computational Optimization; Topology Optimization; Structural Optimization; Heuristic Optimization; ESO; BESO; Optimization Algorithm; Optimization Procedure; Reinforced Concrete Structures; Reinforced Concrete Design; Reinforced Concrete
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
De Marco, A. (. (2018). Application of Evolutionary Structural Optimization to Reinforced Concrete Structures. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:efd1ad24-017f-48ac-8e31-184339a9d148
Chicago Manual of Style (16th Edition):
De Marco, Andrea (author). “Application of Evolutionary Structural Optimization to Reinforced Concrete Structures.” 2018. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:efd1ad24-017f-48ac-8e31-184339a9d148.
MLA Handbook (7th Edition):
De Marco, Andrea (author). “Application of Evolutionary Structural Optimization to Reinforced Concrete Structures.” 2018. Web. 07 Mar 2021.
Vancouver:
De Marco A(. Application of Evolutionary Structural Optimization to Reinforced Concrete Structures. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:efd1ad24-017f-48ac-8e31-184339a9d148.
Council of Science Editors:
De Marco A(. Application of Evolutionary Structural Optimization to Reinforced Concrete Structures. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:efd1ad24-017f-48ac-8e31-184339a9d148

Virginia Tech
7.
Liu, Qiang.
EBF3GLWingOpt: A Framework for Multidisciplinary Design Optimization of Wings Using SpaRibs.
Degree: PhD, Engineering Mechanics, 2014, Virginia Tech
URL: http://hdl.handle.net/10919/49665
► A global/local framework for multidisciplinary optimization of generalized aircraft wing structure has been developed. The concept of curvilinear stiffening members (spars, ribs and stiffeners) has…
(more)
▼ A global/local framework for multidisciplinary
optimization of generalized aircraft wing structure has been developed. The concept of curvilinear stiffening members (spars, ribs and stiffeners) has been applied in the
optimization of a wing structure. A global wing
optimization framework EBF3WingOpt, which integrates the static aeroelastic, flutter and buckling analysis, has been implemented for exploiting the optimal design at the wing level. The wing internal structure is optimized using curvilinear spars and ribs (SpaRibs). A two-step
optimization approach, which consists of topology
optimization with shape design variables and size
optimization with thickness design variables, is implemented in EBF3WingOpt. A local panel
optimization EBF3PanelOpt, which includes stress and buckling evaluation criteria, is performed to optimize the local panels bordered by spars and ribs for further
structural weight saving. The local panel model is extracted from the global finite element model. The boundary conditions are defined on the edges of local panels using the displacement fields obtained from the global model analysis. The local panels are optimized to satisfy stress and buckling constraints. Stiffened panel with curvilinear stiffeners is implemented in EBF3PanelOpt to improve the buckling resistance of the local panels. The
optimization of stiffened panels has been studied and integrated in the local panel
optimization. EBF3WingOpt has been applied for the
optimization of the wing structure of the Boeing N+2 supersonic transport wing and NASA common research model (CRM). The
optimization results have shown the advantage of curvilinear spars and ribs concept. The local panel
optimization EBF3PanelOpt is performed for the NASA CRM wing. The global-local
optimization framework EBF3GLWingOpt, which incorporates global wing
optimization module EBF3WingOpt and local panel
optimization module EBF3PanelOpt, is developed using MATLAB and Python programming to integrate several commercial software: MSC.PATRAN for pre and post processing, MSC.NASTRAN for finite element analysis. An approximate
optimization method is developed for the stiffened panel
optimization so as to reduce the computational cost. The integrated global-local
optimization approach has been applied to subsonic NASA common research model (CRM) wing which proves the methodology's application scaling with medium fidelity FEM analysis. Both the global wing design variables and local panel design variables are optimized to minimize the wing weight at an acceptable computational cost.
Advisors/Committee Members: Kapania, Rakesh K. (committeechair), Hajj, Muhammad R. (committee member), Cramer, Mark S. (committee member), Case, Scott W. (committee member), Patil, Mayuresh J. (committee member).
Subjects/Keywords: Structural Optimization; Global-local Optimization; Wing Optimization; Multidisciplinary Design Optimization; SpaRibs; Stiffened Panel Optimization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Liu, Q. (2014). EBF3GLWingOpt: A Framework for Multidisciplinary Design Optimization of Wings Using SpaRibs. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/49665
Chicago Manual of Style (16th Edition):
Liu, Qiang. “EBF3GLWingOpt: A Framework for Multidisciplinary Design Optimization of Wings Using SpaRibs.” 2014. Doctoral Dissertation, Virginia Tech. Accessed March 07, 2021.
http://hdl.handle.net/10919/49665.
MLA Handbook (7th Edition):
Liu, Qiang. “EBF3GLWingOpt: A Framework for Multidisciplinary Design Optimization of Wings Using SpaRibs.” 2014. Web. 07 Mar 2021.
Vancouver:
Liu Q. EBF3GLWingOpt: A Framework for Multidisciplinary Design Optimization of Wings Using SpaRibs. [Internet] [Doctoral dissertation]. Virginia Tech; 2014. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/10919/49665.
Council of Science Editors:
Liu Q. EBF3GLWingOpt: A Framework for Multidisciplinary Design Optimization of Wings Using SpaRibs. [Doctoral Dissertation]. Virginia Tech; 2014. Available from: http://hdl.handle.net/10919/49665

Carnegie Mellon University
8.
Ulu, Erva.
Enhancing the Structural Performance of Additively Manufactured Objects.
Degree: 2018, Carnegie Mellon University
URL: http://repository.cmu.edu/dissertations/1188
► The ability to accurately quantify the performance an additively manufactured (AM) product is important for a widespread industry adoption of AM as the design is…
(more)
▼ The ability to accurately quantify the performance an additively manufactured (AM) product is important for a widespread industry adoption of AM as the design is required to: (1) satisfy geometrical constraints, (2) satisfy structural constraints dictated by its intended function, and (3) be cost effective compared to traditional manufacturing methods. Optimization techniques offer design aids in creating cost-effective structures that meet the prescribed structural objectives. The fundamental problem in existing approaches lies in the difficulty to quantify the structural performance as each unique design leads to a new set of analyses to determine the structural robustness and such analyses can be very costly due to the complexity of in-use forces experienced by the structure. This work develops computationally tractable methods tailored to maximize the structural performance of AM products. A geometry preserving build orientation optimization method as well as data-driven shape optimization approaches to structural design are presented. Proposed methods greatly enhance the value of AM technology by taking advantage of the design space enabled by it for a broad class of problems involving complex in-use loads.
Subjects/Keywords: additive manufacturing; computational design; fabrication; shape optimization; structural optimization; topology optimization
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APA ·
Chicago ·
MLA ·
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to Zotero / EndNote / Reference
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APA (6th Edition):
Ulu, E. (2018). Enhancing the Structural Performance of Additively Manufactured Objects. (Thesis). Carnegie Mellon University. Retrieved from http://repository.cmu.edu/dissertations/1188
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ulu, Erva. “Enhancing the Structural Performance of Additively Manufactured Objects.” 2018. Thesis, Carnegie Mellon University. Accessed March 07, 2021.
http://repository.cmu.edu/dissertations/1188.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ulu, Erva. “Enhancing the Structural Performance of Additively Manufactured Objects.” 2018. Web. 07 Mar 2021.
Vancouver:
Ulu E. Enhancing the Structural Performance of Additively Manufactured Objects. [Internet] [Thesis]. Carnegie Mellon University; 2018. [cited 2021 Mar 07].
Available from: http://repository.cmu.edu/dissertations/1188.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ulu E. Enhancing the Structural Performance of Additively Manufactured Objects. [Thesis]. Carnegie Mellon University; 2018. Available from: http://repository.cmu.edu/dissertations/1188
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology
9.
Bleker, Lazlo (author).
Hybrid truss layout optimization for generating multiple design alternatives.
Degree: 2021, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:0aace575-f756-4a8b-8cfa-46f788b5a1c3
► As of writing this thesis little research has been done in truss layout optimization for multiple design alternatives. A hybrid scheme is proposed in which…
(more)
▼ As of writing this thesis little research has been done in truss layout
optimization for multiple design alternatives. A hybrid scheme is proposed in which the fast gradient-based search of the Ground Structure Method (GSM) is employed for the search of optimal topology and size, while a population-based meta-heuristic algorithm explores the non-convex parameter space of geometry
optimization. The scheme works by employing a meta-heuristic algorithm to optimize the nodal coordinates of a truss structure where for each iteration and each member of the population a small-scale (i.e. problems with a small number of degrees of freedom) GSM is performed, in order to obtain the optimal topology for the given nodal locations. Three variants of the scheme based on three different meta-heuristic algorithms are developed: Firstly, an Artificial Bee Colony (ABC) and Particle Swarm
Optimization (PSO) variant are developed in combination with an original topology identification method, to extract design alternatives from the solutions found throughout the
optimization process. The developed topology identification method identifies different design alternatives based on topological differences by making use of existing graph isomorphism testing algorithms from graph theory. Additionally, the topology identification method employs a multi-step filtering process to prevent members which are non-critical to the performance of the structure to influence the design alternative selection process. Finally, a Multi-Species Particle Swarm
optimization (MSPSO) variant is developed without the need for a topology identification method. For all methods convergence speed in terms of number of iterations, topological variety and computation time per iteration have been evaluated and are compared. Of the developed methods, the ABC variant converges fastest towards a single good solution, however the topological variety is lacking. The slower converging MSPSO variant produces solutions with moderate topological variety, as well as reasonable material volumes. The PSO variant requires the least computation time per iteration of the developed methods. Its produced topological variety is closer to that of the ABC than the MSPSO variant and it has a slightly faster convergence speed than the MSPSO variant. Direct usage of the MOSEK API is made instead of the more commonly used CVXPY API which reduces GSM problem setup times for small-scale (28 degrees of freedom) problems by a factor of 13. Computation times for the hybrid method, from start to finish, for 3D structures with 4 to 8 movable nodes (12 to 24 geometric degrees of freedom) range from 15 to 50 seconds on standard desktop PC hardware. Because of the multiple design alternative nature of the hybrid method, and consequently the end-user does not require fast back-to-back
optimization runs, these computation times are deemed acceptable. It is concluded that while in its current state the methods based on the hybrid scheme are unlikely to be suitable for usage in practice, further developments…
Advisors/Committee Members: Hendriks, M.A.N. (mentor), Langelaar, M. (graduation committee), van der Linden, L.P.L. (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Ground Structure Method; Layout Optimization; Topology Optimization; Meta-heuristic; Hybrid Optimization; Structural Optimization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Bleker, L. (. (2021). Hybrid truss layout optimization for generating multiple design alternatives. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:0aace575-f756-4a8b-8cfa-46f788b5a1c3
Chicago Manual of Style (16th Edition):
Bleker, Lazlo (author). “Hybrid truss layout optimization for generating multiple design alternatives.” 2021. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:0aace575-f756-4a8b-8cfa-46f788b5a1c3.
MLA Handbook (7th Edition):
Bleker, Lazlo (author). “Hybrid truss layout optimization for generating multiple design alternatives.” 2021. Web. 07 Mar 2021.
Vancouver:
Bleker L(. Hybrid truss layout optimization for generating multiple design alternatives. [Internet] [Masters thesis]. Delft University of Technology; 2021. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:0aace575-f756-4a8b-8cfa-46f788b5a1c3.
Council of Science Editors:
Bleker L(. Hybrid truss layout optimization for generating multiple design alternatives. [Masters Thesis]. Delft University of Technology; 2021. Available from: http://resolver.tudelft.nl/uuid:0aace575-f756-4a8b-8cfa-46f788b5a1c3

Universitat Politècnica de València
10.
Sánchez Caballero, Samuel.
Optimización estructural y topológica de estructuras morfológicamente no definidas mediante algoritmos genéticos
.
Degree: 2012, Universitat Politècnica de València
URL: http://hdl.handle.net/10251/15409
► La optimización de estructuras ha sido una disciplina muy estudiada por numerosos investigadores durante los últimos cuarenta años. A pesar de que durante los primeros…
(more)
▼ La optimización de estructuras ha sido una disciplina muy estudiada por numerosos investigadores durante los últimos cuarenta años. A pesar de que durante los primeros veinte años las técnicas de Programación Matemática fueron la herramienta fundamental en este campo, estas han ido perdiendo fuelle frente a un nuevo conjunto de técnicas metaheurísticas basadas en la Computación Evolutiva. De entre destacan, de manera significativa, los Algoritmos Genéticos.
La irrupción de estas nuevas técnicas en el campo de la optimización de estructuras es debida, en gran medida, a las dificultades de la programación matemática para realizar la optimización simultánea de las variables de diseño debido a la elevada alinealidad de estas y sus restricciones
El objetivo fundamental del presente trabajo es ir un poco más allá en el proceso de la optimización simultánea de las variables de diseño, definiendo un algoritmo que no parte de una estructura predefinida y que incorpora los parámetros que determinan la geometría. A diferencia de los métodos actuales, el algoritmo desarrollado no requiere de ningún tipo de estructura inicial ni otro tipo de información adicional, aparte de la definición de los puntos de aplicación de las cargas, los puntos de apoyo y el tipo de apoyo.
El nuevo algoritmo desarrollado se justifica según la siguiente hipótesis: La definición previa de la forma, geometría, regla o modelo preconcebido en una estructura suponen restricciones del diseño en sí mismas y por lo tanto aquel algoritmo que no se encuentre sujeto a estas deberá poder generar diseños necesariamente mejores, o al menos tan buenos como los existentes.
A partir de esta hipótesis se desarrolla un nuevo algoritmo con una codificación mixta, adaptada a cada grupo de variables de diseño, donde los diferentes operadores se definen y actúan de forma independiente para grupo.
Advisors/Committee Members: Segui Llinares, Vicente Jesús (advisor), Crespo Amorós, José Enrique (advisor), Sellés Cantó, Miguel Ángel (advisor).
Subjects/Keywords: Genetic;
Algorithm;
Structural;
Simultaneous;
Optimization;
Artificial;
Intelligence
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sánchez Caballero, S. (2012). Optimización estructural y topológica de estructuras morfológicamente no definidas mediante algoritmos genéticos
. (Doctoral Dissertation). Universitat Politècnica de València. Retrieved from http://hdl.handle.net/10251/15409
Chicago Manual of Style (16th Edition):
Sánchez Caballero, Samuel. “Optimización estructural y topológica de estructuras morfológicamente no definidas mediante algoritmos genéticos
.” 2012. Doctoral Dissertation, Universitat Politècnica de València. Accessed March 07, 2021.
http://hdl.handle.net/10251/15409.
MLA Handbook (7th Edition):
Sánchez Caballero, Samuel. “Optimización estructural y topológica de estructuras morfológicamente no definidas mediante algoritmos genéticos
.” 2012. Web. 07 Mar 2021.
Vancouver:
Sánchez Caballero S. Optimización estructural y topológica de estructuras morfológicamente no definidas mediante algoritmos genéticos
. [Internet] [Doctoral dissertation]. Universitat Politècnica de València; 2012. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/10251/15409.
Council of Science Editors:
Sánchez Caballero S. Optimización estructural y topológica de estructuras morfológicamente no definidas mediante algoritmos genéticos
. [Doctoral Dissertation]. Universitat Politècnica de València; 2012. Available from: http://hdl.handle.net/10251/15409

Delft University of Technology
11.
Luitse, S.J.J. (author).
Deconstruction: A new construction method for prefabricated shell structures.
Degree: 2016, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:ec1f51d5-2e38-47ac-98ca-dc8045a94bd6
► Shell structures are expensive structures due to their extensive construction time and costs making them unpopular in spite of their material and structural efficiency. Temporary…
(more)
▼ Shell structures are expensive structures due to their extensive construction time and costs making them unpopular in spite of their material and structural efficiency. Temporary support structures are now based on the weight of the structure without taking into account what the incomplete structure can carry by itself. Structural characteristics of shell structures and modern computational methods do provide a solid platform to optimize the construction procedure of these nature adaptive and esthetically pleasing structures. This would save time and money through exclusion of set up time, reduced scaffolding costs and enabling of simultaneous construction phasing (building under the roof while the roof is being build). Recent research into historical and newly available methods has unveiled methods to nearly exclude the use of temporary support. However, these methods have not been tested on large scale designs and do not prove to be fit for up scaling. In the last five years structural patterning and the influence of a panel pattern on force flow have also come up as a research field for building construction. A combination of features found in past methods and recent research can be joined into an improved modern construction method. To know the minimal amount of supports needed the structure will need to be monitored every step of the construction process. Simultaneously it will have to find the best panel to put in next. To retrieve this information from the ground up, every panel that can possibly be installed will need to be tested. On large scale projects this will be a time costly process. That is why Ir. P. Eigenraam and Msc. S. Luitse have developed their own method: Deconstruction and reversed Deconstruction. Deconstruction is the initial analysis method that works from the top, the complete assembled structure, down. Based on a finite element analysis (FEA) at each iteration it finds the least stressed panel and removes it. This can be compared to finding the loosest block in Jenga. This will continue until the structure is fully deconstructed. This will provide a reversed construction order that can be used to construct the structure with the least amount of stress and deformation. This construction method is called reversed Deconstruction. Although the deconstruction algorithm is still under development first analysis show up to 75% reductions of temporary supports during construction. Further reductions can be done by preassembling parts of the structure. This report will research the possibilities of this analysis and construction method. A historical review of shell construction methods combined with research into force flow through complex free form prefabricated shell structures will provide the pointers and tools. Along these pointers and tools the Deconstruction analysis method will be set up. The method is tested through FEA and concluded upon. It is the search for a smart construction method.
Architecture and The Built Environment
Building Technology
Advisors/Committee Members: Eigenraam, P. (mentor).
Subjects/Keywords: deconstruction; algorithmic; construction optimization; structural design
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Luitse, S. J. J. (. (2016). Deconstruction: A new construction method for prefabricated shell structures. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:ec1f51d5-2e38-47ac-98ca-dc8045a94bd6
Chicago Manual of Style (16th Edition):
Luitse, S J J (author). “Deconstruction: A new construction method for prefabricated shell structures.” 2016. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:ec1f51d5-2e38-47ac-98ca-dc8045a94bd6.
MLA Handbook (7th Edition):
Luitse, S J J (author). “Deconstruction: A new construction method for prefabricated shell structures.” 2016. Web. 07 Mar 2021.
Vancouver:
Luitse SJJ(. Deconstruction: A new construction method for prefabricated shell structures. [Internet] [Masters thesis]. Delft University of Technology; 2016. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:ec1f51d5-2e38-47ac-98ca-dc8045a94bd6.
Council of Science Editors:
Luitse SJJ(. Deconstruction: A new construction method for prefabricated shell structures. [Masters Thesis]. Delft University of Technology; 2016. Available from: http://resolver.tudelft.nl/uuid:ec1f51d5-2e38-47ac-98ca-dc8045a94bd6

Delft University of Technology
12.
Winklaar, M. (author).
Optimization of the structural grid tessellation for multi curved surface.
Degree: 2012, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:9e3f83f0-1f87-4c1a-8b2b-142d29020a7d
► "Optimization of the structural grid tessellation for multi curved surface" is the graduation thesis that research and develop a design tool that generated different tessellation…
(more)
▼ "Optimization of the structural grid tessellation for multi curved surface" is the graduation thesis that research and develop a design tool that generated different tessellation patterns on any given multi curved surface, which will then be optimized and analyse for the best structural performance.
Computation & Performance
Building Technology
Architecture
Advisors/Committee Members: Turrin, M. (mentor), Borgart, A. (mentor).
Subjects/Keywords: Tessellation Generator; Dynamic Relaxation; Structural Optimization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Winklaar, M. (. (2012). Optimization of the structural grid tessellation for multi curved surface. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:9e3f83f0-1f87-4c1a-8b2b-142d29020a7d
Chicago Manual of Style (16th Edition):
Winklaar, M (author). “Optimization of the structural grid tessellation for multi curved surface.” 2012. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:9e3f83f0-1f87-4c1a-8b2b-142d29020a7d.
MLA Handbook (7th Edition):
Winklaar, M (author). “Optimization of the structural grid tessellation for multi curved surface.” 2012. Web. 07 Mar 2021.
Vancouver:
Winklaar M(. Optimization of the structural grid tessellation for multi curved surface. [Internet] [Masters thesis]. Delft University of Technology; 2012. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:9e3f83f0-1f87-4c1a-8b2b-142d29020a7d.
Council of Science Editors:
Winklaar M(. Optimization of the structural grid tessellation for multi curved surface. [Masters Thesis]. Delft University of Technology; 2012. Available from: http://resolver.tudelft.nl/uuid:9e3f83f0-1f87-4c1a-8b2b-142d29020a7d

Delft University of Technology
13.
Hidding, A.J. (author).
Continuous Exploration.
Degree: 2016, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:a19f0348-7b8f-4569-b8a2-7af8e719d629
► The goal of the design studio is to formulate a design proposal for a 7000 m2 pavilion for the World Expo in 2025 in Rotterdam.…
(more)
▼ The goal of the design studio is to formulate a design proposal for a 7000 m2 pavilion for the World Expo in 2025 in Rotterdam. The theme of the world expo is: where ambition turns environmental challenges into economic opportunities. The building industry is a large polluter, since manufacturing processes cause a lot of waste and has a high energy consumption. The paradigm shift from mass standardization to mass customization is made possible by the third industrial revolution, namely the robotization of the manufacturing industry. When the manufacturing processes in the building industry are robotized this could reduce energy consumption, reduce waste, increase efficiency and use less materials while allowing humans to specialize. Robotic devices are already being used in the manufacturing industry, but they are not being used to their full potential. The tasks they are most commonly given are repetitive, because of limitations in the software and willingness/knowledge of manufactures. The pavilion should showcase the development of the robotic devices that will allow for mass customization in the building industry. ROS industrial consortium is a developer of open source robotic software and apply the software to the manufacturing industry. During the World Expo, the ROS industrial consortium will exhibit the newest technologies and showcase the major developments. After the World Expo the pavilion will be used as a research, education and conference centre by ROS. Research questions - In what way can the pavilion be shaped so the visitor will be stimulated to explore the pavilion and its exhibitions? - In what way can the paths to the pavilion and inside the pavilion be shaped to account for these people flows? - The inhabitants of the Noordereiland in Rotterdam appreciate the park space on the chosen site. In what way can the pavilion be placed to maintain or improve the qualities that are present on the site?
Architecture and The Built Environment
Architectural Engineering +Technology
Hyperbody
Advisors/Committee Members: Bier, H.H. (mentor), Vollers, K.J. (mentor), Mostafavi, S. (mentor).
Subjects/Keywords: hyperbody; porosity; structural optimization; robotic production; d2rp
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hidding, A. J. (. (2016). Continuous Exploration. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:a19f0348-7b8f-4569-b8a2-7af8e719d629
Chicago Manual of Style (16th Edition):
Hidding, A J (author). “Continuous Exploration.” 2016. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:a19f0348-7b8f-4569-b8a2-7af8e719d629.
MLA Handbook (7th Edition):
Hidding, A J (author). “Continuous Exploration.” 2016. Web. 07 Mar 2021.
Vancouver:
Hidding AJ(. Continuous Exploration. [Internet] [Masters thesis]. Delft University of Technology; 2016. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:a19f0348-7b8f-4569-b8a2-7af8e719d629.
Council of Science Editors:
Hidding AJ(. Continuous Exploration. [Masters Thesis]. Delft University of Technology; 2016. Available from: http://resolver.tudelft.nl/uuid:a19f0348-7b8f-4569-b8a2-7af8e719d629

Delft University of Technology
14.
Tromp, J.M. (author).
The Effect of Braces in an Asymmetric Semi-Submersible Hull: A Structural Weight and Multiaxial Fatigue Assessment.
Degree: 2016, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:7dc23b81-ad4a-41b0-88c6-6b97641547e9
► Heerema Marine Contractors is looking into a new semi-submersible crane vessel concept with an asymmetric hull. The necessity of braces (connections between the portside and…
(more)
▼ Heerema Marine Contractors is looking into a new semi-submersible crane vessel concept with an asymmetric hull. The necessity of braces (connections between the portside and starboard hulls) for this vessel is questioned, based on earlier vessel developments and operational experience. This study addresses the influence of braces on the structural integrity of the hull. The influence is examined by performing a hydrodynamic, strength and fatigue analysis. The aim of this thesis is comparative; what is the difference between a structural configuration with and a configuration without braces is the red line through this thesis. The structural governing sea states are found using a spectral analysis. A structural optimization in the strength analysisis performed using MATLAB optimization tools. High braces weights are found for which the physical explanations are: 1) the magnitude of the main particulars of the vessel and 2) the fact that a 'forced' displacement is created on the edge nodes of the braces causing very high bending and shear loads. Braces also influence the structural behavior in other parts of the vessel. Therefore the fatigue damage in a deckbox column connection is considered using: 1) a principal stress method and 2) a multiaxial method using Path Dependent Maximum Range (PDMR) cycle counting.It was found that a configuration without braces will yield higher fatigue damages in considered detail in both approaches. The multi-axial approach showed to be the conservative method.
Mechanical, Maritime and Materials Engineering
Maritime and Transport Technology - Offshore and Dredging Engineering - Structural Analysis and Design
Advisors/Committee Members: Kaminski, M.L. (mentor), Van Lieshout, P.S. (mentor).
Subjects/Keywords: semi-submersible; structural optimization; multiaxial fatigue
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Tromp, J. M. (. (2016). The Effect of Braces in an Asymmetric Semi-Submersible Hull: A Structural Weight and Multiaxial Fatigue Assessment. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:7dc23b81-ad4a-41b0-88c6-6b97641547e9
Chicago Manual of Style (16th Edition):
Tromp, J M (author). “The Effect of Braces in an Asymmetric Semi-Submersible Hull: A Structural Weight and Multiaxial Fatigue Assessment.” 2016. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:7dc23b81-ad4a-41b0-88c6-6b97641547e9.
MLA Handbook (7th Edition):
Tromp, J M (author). “The Effect of Braces in an Asymmetric Semi-Submersible Hull: A Structural Weight and Multiaxial Fatigue Assessment.” 2016. Web. 07 Mar 2021.
Vancouver:
Tromp JM(. The Effect of Braces in an Asymmetric Semi-Submersible Hull: A Structural Weight and Multiaxial Fatigue Assessment. [Internet] [Masters thesis]. Delft University of Technology; 2016. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:7dc23b81-ad4a-41b0-88c6-6b97641547e9.
Council of Science Editors:
Tromp JM(. The Effect of Braces in an Asymmetric Semi-Submersible Hull: A Structural Weight and Multiaxial Fatigue Assessment. [Masters Thesis]. Delft University of Technology; 2016. Available from: http://resolver.tudelft.nl/uuid:7dc23b81-ad4a-41b0-88c6-6b97641547e9

Michigan State University
15.
Fuchi, Kazuko.
Optimization of electromagnetic devices and materials.
Degree: 2012, Michigan State University
URL: http://etd.lib.msu.edu/islandora/object/etd:1204
► Thesis Ph. D. Michigan State University. Mechanical Engineering 2012.
Topology optimization is a computational design methodology that is used to find topologies of optimal design,…
(more)
▼ Thesis Ph. D. Michigan State University. Mechanical Engineering 2012.
Topology optimization is a computational design methodology that is used to find topologies of optimal design, that match design goals. Application of topology optimization in the area of electromagnetics is extremely interesting, since for many electromagnetic design problems the topology of inclusion structures in materials or components in devices can have a dramatic effect on the interaction of the designed structure with the electromagnetic waves. The success of the use of topology optimization for design of metamaterials, antennas, waveguides, etc. reported in literature suggests the importance of research into effective uses of topology optimization in electromagnetic design problems.The purpose of this dissertation is to investigate efficient electromagnetic analysis methods that can be combined with the method of topology optimization, as well as to develop a new way of using topology optimization to design electromagnetic devices with transformable complex surface geometry, using the concept of origami.The first part of the dissertation focuses on the investigation of a topology optimization framework for design of periodic structures for electromagnetic applications, using a rigorous and efficient finite element analysis method. The second part introduces a topology optimization based design method for origami folding patterns. To illustrate its use, the origami design method is employed to design frequency selective surfaces for electromagnetic applications, that can transform in their surface geometry to alter their working frequency through folding and unfolding.
Description based on online resource; title from PDF t.p. (ProQuest, viewed June 10, 2013)
Advisors/Committee Members: Diaz, Alejandro R, Rothwell, Edward J, Choi, Jongeun, Baek, Seungik.
Subjects/Keywords: Structural optimization; Topology; Electromagnetic waves; Mechanical engineering
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Fuchi, K. (2012). Optimization of electromagnetic devices and materials. (Thesis). Michigan State University. Retrieved from http://etd.lib.msu.edu/islandora/object/etd:1204
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Fuchi, Kazuko. “Optimization of electromagnetic devices and materials.” 2012. Thesis, Michigan State University. Accessed March 07, 2021.
http://etd.lib.msu.edu/islandora/object/etd:1204.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Fuchi, Kazuko. “Optimization of electromagnetic devices and materials.” 2012. Web. 07 Mar 2021.
Vancouver:
Fuchi K. Optimization of electromagnetic devices and materials. [Internet] [Thesis]. Michigan State University; 2012. [cited 2021 Mar 07].
Available from: http://etd.lib.msu.edu/islandora/object/etd:1204.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Fuchi K. Optimization of electromagnetic devices and materials. [Thesis]. Michigan State University; 2012. Available from: http://etd.lib.msu.edu/islandora/object/etd:1204
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology
16.
Vuik, Nelleke (author).
Structural Optimization of the Monopile Installation Frame Design.
Degree: 2018, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:6411fc4d-2cf6-465e-9fae-34951cab5d36
► Wind energy plays an important role in the global energy supply and is obtained by wind turbines placed on- and offshore. The expected growth of…
(more)
▼ Wind energy plays an important role in the global energy supply and is obtained by wind turbines placed on- and offshore. The expected growth of offshore wind farms will generate a lot of work in the future. Seaway Heavy Lifting is an offshore company which offers Engineering, Procurement, Construction and Installation (EPCI) solutions worldwide for oil, gas and renewables projects. Offshore wind turbines are most commonly placed on a monopile foundation. The installation of monopile foundations used for offshore wind turbine farms is the main part of the projects Seaway Heavy Lifting is executing. The installation of monopiles is done using an installation vessel, which needs to be anchored during installation. The anchoring is done in order to cooperate with external forces on the side shell due to the installation of the monopile. The installation of the monopile is done using a frame which is connected to the side shell of the vessel. In order to stay competitive in the business, the company has been doing research to how to decrease the amount of installation time of their projects. It is concluded that profit can be gained by reducing the necessary time to anchor the installation vessel. To install monopiles without anchoring the vessel, the monopile installation frame (MIF) was designed. The MIF can be placed onto the seabed after which the monopile can be hoisted inside of the frame. The frame will support the monopile during hammering. No external forces will be acting on the side shell of the vessel when using the MIF during hammering, which rules out the need for anchoring the vessel. Instead of anchoring, dynamic positioning will be used. Since the installation of monopiles will occur in different water depths, the MIF needs to be modular. An extension piece will be used in order to change the height of the frame. The goal of this thesis is to obtain a
structural optimized design of the MIF. The connections needed to connect and disconnect the extension piece are critical sections of the MIF. During the lifetime of the MIF, fatigue due to waves, wind and current loading will play a role. Therefore, this thesis has focused on the
structural optimization of the connection with respect to fatigue loading. A bolted flange connection will be used in order to connect the members, which will be machined and then welded to the tube end. An initial geometry of the connection was designed with help of design rules stated by ir. M. Seidel. The finite element program ANSYS will be used for the calculation of stress distributions. The decision was made to verify ANSYS, which was done by studying the accuracy of ANSYS, its way of working and to get used to the program. The verification has been done using a reference project. The fatigue analysis of the connection started first of all with a global load analysis. This was done with help of the program SACS, which uses wave heights and wind speeds together with currents data as input. A calculation model of the MIF was…
Advisors/Committee Members: Hendriks, Max (mentor), Veljkovic, Milan (mentor), Abspoel, Roland (mentor), Houben, Lambert (mentor), Delft University of Technology (degree granting institution).
Subjects/Keywords: Structural Optimization; Fatigue Analysis; Steel Structures
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Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Vuik, N. (. (2018). Structural Optimization of the Monopile Installation Frame Design. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:6411fc4d-2cf6-465e-9fae-34951cab5d36
Chicago Manual of Style (16th Edition):
Vuik, Nelleke (author). “Structural Optimization of the Monopile Installation Frame Design.” 2018. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:6411fc4d-2cf6-465e-9fae-34951cab5d36.
MLA Handbook (7th Edition):
Vuik, Nelleke (author). “Structural Optimization of the Monopile Installation Frame Design.” 2018. Web. 07 Mar 2021.
Vancouver:
Vuik N(. Structural Optimization of the Monopile Installation Frame Design. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:6411fc4d-2cf6-465e-9fae-34951cab5d36.
Council of Science Editors:
Vuik N(. Structural Optimization of the Monopile Installation Frame Design. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:6411fc4d-2cf6-465e-9fae-34951cab5d36

Rutgers University
17.
Song, Wei, 1981-.
Domain composition method and its applications.
Degree: Mechanical and Aerospace Engineering, 2014, Rutgers University
URL: https://rucore.libraries.rutgers.edu/rutgers-lib/42451/
Subjects/Keywords: Structural optimization; Topology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Song, Wei, 1. (2014). Domain composition method and its applications. (Thesis). Rutgers University. Retrieved from https://rucore.libraries.rutgers.edu/rutgers-lib/42451/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Song, Wei, 1981-. “Domain composition method and its applications.” 2014. Thesis, Rutgers University. Accessed March 07, 2021.
https://rucore.libraries.rutgers.edu/rutgers-lib/42451/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Song, Wei, 1981-. “Domain composition method and its applications.” 2014. Web. 07 Mar 2021.
Vancouver:
Song, Wei 1. Domain composition method and its applications. [Internet] [Thesis]. Rutgers University; 2014. [cited 2021 Mar 07].
Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/42451/.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Song, Wei 1. Domain composition method and its applications. [Thesis]. Rutgers University; 2014. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/42451/
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
18.
Munro, Dirk Pieter.
A direct approach to structural topology optimization.
Degree: PhD, Mechanical and Mechatronic Engineering, 2017, Stellenbosch University
URL: http://hdl.handle.net/10019.1/101051
► ENGLISH ABSTRACT: This dissertation addresses various topics that emerge from the unification of conventional structural optimization—based on ‘sequential approximate optimization’ (SAO)—with the alternative ‘direct’—or ‘simultaneous…
(more)
▼ ENGLISH ABSTRACT: This dissertation addresses various topics that emerge from the unification of conventional
structural
optimization—based on ‘sequential approximate optimization’ (SAO)—with the alternative
‘direct’—or ‘simultaneous analysis and design’ (SAND)—formulation of the
structural
topology design problem.
Structural topology optimization—in the form of a ‘material distribution
problem’—is a generalisation of
structural optimization, encompassing and simultaneously
addressing al the aspects of
structural design. In
structural optimization, SAO techniques
are preferred because the number of
structural analyses—which are expensive, computationally
speaking—are ostensibly minimised. However, particularly in the presence of local state-based
constraints—e.g. local stress constraints—the sensitivity analyses which accompany traditional
‘nested analysis an design’ (NAND) methods require a prohibitive number of
structural analysis
runs per design iteration.
In the alternative SAND setting,
structural analysis is conducted approximately and sequentially:
the finite element (FE) equilibrium equations are retained as a set of nonlinear equality
constraints and the state variables—i.e. displacements—form part of the overall set of primal
variables. Therefore, the FE equilibrium equations may only be satisfied at convergence of
the
optimization algorithm, and the complex and expensive sensitivity analyses associated with
state-based constraints, simplify to the calculation of partial derivatives. Moreover, the equivalent
of a single
structural analysis only is required per design iteration, notwithstanding the
imposition of a large number of state-based constraints.
Based on a dual method in theory, we propose a separable and strictly convex quadratic
Lagrange-Newton approximate subproblem for use in SAO of the SAND formulated topology
design problem. In classical (simply-constrained) minimum compliance design, the dual statement
of the subproblem is equivalent to the ever-popular optimality criteria (OC) approach—a
class of NAND methods. This relates, in turn, to the known equivalence between dual SAONAND
algorithms based on intervening variables and the OC method.
Due to the presence of nonlinear equality constraints, the classical SAO procedure (exclusively
geared, traditionally, for inequality constrained problems) is extended to a general, nonlinear
and nonconvex, mathematical programming framework. It turns out that conventional techniques of enforced convergence and termination in traditional NAND-based SAO may be
transplanted into the SAND setting with only minor complications.
It is demonstrated that the compounded issues of existence of solutions, mesh-dependence,
local minima, and macro-scale manufacturability, may be addressed in a computationally efficient
manner by the imposition of so-called ‘slope constraints’—point-wise bounds on the
gradient of the material distribution function. For global
optimization, random multistart strategies
may be pursued. A specialized version…
Advisors/Committee Members: Groenwold, Albert A., Stellenbosch University. Faculty of Engineering. Dept. of Mechanical and Mechatronic Engineering..
Subjects/Keywords: Structural design.; SAO (Sequential approximation optimization); Convex programming; Design services; Structural optimization; UCTD
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Munro, D. P. (2017). A direct approach to structural topology optimization. (Doctoral Dissertation). Stellenbosch University. Retrieved from http://hdl.handle.net/10019.1/101051
Chicago Manual of Style (16th Edition):
Munro, Dirk Pieter. “A direct approach to structural topology optimization.” 2017. Doctoral Dissertation, Stellenbosch University. Accessed March 07, 2021.
http://hdl.handle.net/10019.1/101051.
MLA Handbook (7th Edition):
Munro, Dirk Pieter. “A direct approach to structural topology optimization.” 2017. Web. 07 Mar 2021.
Vancouver:
Munro DP. A direct approach to structural topology optimization. [Internet] [Doctoral dissertation]. Stellenbosch University; 2017. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/10019.1/101051.
Council of Science Editors:
Munro DP. A direct approach to structural topology optimization. [Doctoral Dissertation]. Stellenbosch University; 2017. Available from: http://hdl.handle.net/10019.1/101051

University of Arizona
19.
Trondsen, Torvald, 1933-.
Optimum design methods
.
Degree: 1969, University of Arizona
URL: http://hdl.handle.net/10150/318774
Subjects/Keywords: Structural optimization.;
Structural analysis (Engineering)
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Trondsen, Torvald, 1. (1969). Optimum design methods
. (Masters Thesis). University of Arizona. Retrieved from http://hdl.handle.net/10150/318774
Chicago Manual of Style (16th Edition):
Trondsen, Torvald, 1933-. “Optimum design methods
.” 1969. Masters Thesis, University of Arizona. Accessed March 07, 2021.
http://hdl.handle.net/10150/318774.
MLA Handbook (7th Edition):
Trondsen, Torvald, 1933-. “Optimum design methods
.” 1969. Web. 07 Mar 2021.
Vancouver:
Trondsen, Torvald 1. Optimum design methods
. [Internet] [Masters thesis]. University of Arizona; 1969. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/10150/318774.
Council of Science Editors:
Trondsen, Torvald 1. Optimum design methods
. [Masters Thesis]. University of Arizona; 1969. Available from: http://hdl.handle.net/10150/318774

Delft University of Technology
20.
Goeijenbier, Bart (author).
Structural Optimisation and Behaviour of the Breakwater Integrated Oscillating Water Column Device: A Combined 3D CFD and Structural Analysis.
Degree: 2020, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:b05906aa-691f-42ff-8369-4a3c3a77f7a9
► The Oscillating Water Column (OWC) device is one of many available technologies for generating electricity from water waves. It is a caisson-like structure, which houses…
(more)
▼ The Oscillating Water Column (OWC) device is one of many available technologies for generating electricity from water waves. It is a caisson-like structure, which houses a water column in an enclosed chamber with an inlet at the bottom. Waves enter the device, exciting the water column. The trapped air above is forced out through a turbine, generating electricity. The technology is relatively young compared to other sources of renewable energy, such as solar or wind energy. This makes the produced energy expensive, expressed in the Levelised Cost of Energy (LCOE). Integrating devices into breakwaters already resulted in a large reduction of the costs, as they now can be shared. During the design of such devices, main attention is given to the geometrical design. This should be based on local wave conditions to ensure the largest energy production. Having the eigenperiod match with the incident wave period enhances the resonance effect in the chamber. This research explores the potential to reduce the costs of OWC devices integrated in breakwaters through means of structural optimisation. The structural are built quite robust, leaving the thought there is room for improvement. The device in Civitavecchia, Italy was used as a case study. A new method was adopted to investigate the potential. A numerical model was constructed in STAR-CCM+, including both a fluid domain and a solid domain. The two are one-way coupled, from water to structure. The exerted wave pressures are mapped on the structure directly, resulting in a stress state in the OWC structure. Due to the transient nature of the simulations, all results are available through time. It was found, the main walls shaping the OWC device could be built with 35% less material. Variants of the original geometry were tested as well to see how these influence the results. Furthermore, the structural behaviour was investigated. Clear trends were found in position and timing of governing load combinations in the different walls. One of the most important findings was that the governing load case always was in the direction of the transverse width. The walls were found to behave more like beams in this direction. The bending moments could therefore easily be calculated using standard beam equations and the net horizontal pressure on the wall as load. This leads to the beginning of a new simplified design method where the full numerical structural analysis is not required anymore.
Civil Engineering | Structural Engineering | Hydraulic Structures
Advisors/Committee Members: Antonini, A. (mentor), Bricker, J.D. (graduation committee), van der Ham, H.W.M. (graduation committee), Hendriks, M.A.N. (graduation committee), Malara, Giovanni (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Oscillating Water Column (OWC); Structural Optimization; Structural Behavior; Numerical modelling
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Goeijenbier, B. (. (2020). Structural Optimisation and Behaviour of the Breakwater Integrated Oscillating Water Column Device: A Combined 3D CFD and Structural Analysis. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:b05906aa-691f-42ff-8369-4a3c3a77f7a9
Chicago Manual of Style (16th Edition):
Goeijenbier, Bart (author). “Structural Optimisation and Behaviour of the Breakwater Integrated Oscillating Water Column Device: A Combined 3D CFD and Structural Analysis.” 2020. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:b05906aa-691f-42ff-8369-4a3c3a77f7a9.
MLA Handbook (7th Edition):
Goeijenbier, Bart (author). “Structural Optimisation and Behaviour of the Breakwater Integrated Oscillating Water Column Device: A Combined 3D CFD and Structural Analysis.” 2020. Web. 07 Mar 2021.
Vancouver:
Goeijenbier B(. Structural Optimisation and Behaviour of the Breakwater Integrated Oscillating Water Column Device: A Combined 3D CFD and Structural Analysis. [Internet] [Masters thesis]. Delft University of Technology; 2020. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:b05906aa-691f-42ff-8369-4a3c3a77f7a9.
Council of Science Editors:
Goeijenbier B(. Structural Optimisation and Behaviour of the Breakwater Integrated Oscillating Water Column Device: A Combined 3D CFD and Structural Analysis. [Masters Thesis]. Delft University of Technology; 2020. Available from: http://resolver.tudelft.nl/uuid:b05906aa-691f-42ff-8369-4a3c3a77f7a9

Duke University
21.
Sanders, Clay Michael.
Inverse-Problem Inspired Approaches in the Design of Solids for Frequency-Domain Dynamics
.
Degree: 2020, Duke University
URL: http://hdl.handle.net/10161/21500
► Dynamic conditions and harmful vibration are prevalent in many engineered systems. Computational optimization methods can usefully guide the design of structures and solid systems…
(more)
▼ Dynamic conditions and harmful vibration are prevalent in many engineered systems. Computational
optimization methods can usefully guide the design of structures and solid systems to obtain layouts with desired dynamic behaviors, such as minimized or tailored vibration response, while accounting for additional constraints. Due to resonance phenomena in steady-state dynamics, however, objectives used to control dynamic response possess many local minima that may represent poor solutions to a design problem, causing challenges for gradient-based
optimization methods. Additionally, designs are typically characterized by high-dimensional parameter spaces, which require costly regularization operations and can lead to slow convergence. This dissertation presents strategies to address these obstacles in dynamic response design problems, seeking inspiration from solution strategies for the related class of medium inversion problems. We propose an extension of the modified error in constitutive equations (MECE) method, used previously in material identification problems, as a new approach for frequency-domain dynamics topology
optimization to mitigate solution dependence upon initial guess and considered loading conditions. The main idea of the MECE strategy is to relax the constitutive relations between stresses and strains and between inertial forces and displacements in the elastodynamic PDE-constraint. An additional penalty-like term measuring the discrepancy in these relations is added to the objective, so that both model error and the original response objective are minimized. The resulting
optimization problem features an objective more amenable to minimization, as resonant responses are suppressed in the relaxed elastodynamic model. We show that this approach yields superior designs to conventional gradient-based
optimization approaches that solely use a functional of displacements as the objective, while strictly enforcing the constitutive equations. We highlight the merits of our approach in a variety of scenarios for direct frequency response design, considering multiple frequency load cases and different frequency-response control objectives. We next present an adaptive eigenspace basis (AEB) strategy for effective design dimensionality reduction in topology
optimization problems. We construct the density field as a linear combination of eigenfunctions, computed for an elliptic operator defined over the design domain, and solve for the associated eigenfunction coefficients. Restriction to this finite-dimensional eigenspace drastically reduces the design dimension and imposes implicit regularization upon the solution. We furthermore develop a basis adaptation scheme, in which we iteratively recompute the eigenfunction basis to conform to the evolving solution field, enabling further dimension reduction and acceleration of the
optimization process. We demonstrate the AEB method on topology
optimization problems for static linear elasticity, benchmarking its performance against conventional TO…
Advisors/Committee Members: Aquino, Wilkins (advisor).
Subjects/Keywords: Engineering;
Computational Mechanics;
Structural Design;
Structural Dynamics;
Topology Optimization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Sanders, C. M. (2020). Inverse-Problem Inspired Approaches in the Design of Solids for Frequency-Domain Dynamics
. (Thesis). Duke University. Retrieved from http://hdl.handle.net/10161/21500
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Sanders, Clay Michael. “Inverse-Problem Inspired Approaches in the Design of Solids for Frequency-Domain Dynamics
.” 2020. Thesis, Duke University. Accessed March 07, 2021.
http://hdl.handle.net/10161/21500.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Sanders, Clay Michael. “Inverse-Problem Inspired Approaches in the Design of Solids for Frequency-Domain Dynamics
.” 2020. Web. 07 Mar 2021.
Vancouver:
Sanders CM. Inverse-Problem Inspired Approaches in the Design of Solids for Frequency-Domain Dynamics
. [Internet] [Thesis]. Duke University; 2020. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/10161/21500.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Sanders CM. Inverse-Problem Inspired Approaches in the Design of Solids for Frequency-Domain Dynamics
. [Thesis]. Duke University; 2020. Available from: http://hdl.handle.net/10161/21500
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
22.
Gaynor, Andrew Thomas.
Topology Optimization Algorithms for Additive Manufacturing.
Degree: 2015, Johns Hopkins University
URL: http://jhir.library.jhu.edu/handle/1774.2/38009
► Topology optimization is a powerful free-form design tool that couples finite element analysis with mathematical programming to systematically design for any number of engineering problems.…
(more)
▼ Topology
optimization is a powerful free-form design tool that couples finite element analysis with mathematical programming to systematically design for any number of engineering problems. Additive manufacturing (AM), specifically 3D printing, is a manufacturing process where material is added through deposition or melting in a layer-by-layer fashion. Additively manufactured parts are `built' from the bottom up, allowing production of intricate designs without extra effort on the part of the engineer or technician – complexity is often said to be `free'. This dissertation seeks to leverage the full potential of this burgeoning manufacturing technology by developing several new design algorithms based on topology
optimization. These include multi-material projection methods appropriate for multiphase 3D printers, an overhang-prevention projection method capable of designing components that do not need sacrificial anchors in metal AM processes, and models for
simultaneously optimizing topology and objects embedded in process. These algorithms are demonstrated on several design examples and shown to produce solutions with capabilities that exceed existing designs and/or that require less post-processing in fabrication. Targeting the capabilities of the Polyjet Stratasys 3D printers, a topology
optimization algorithm is developed for the design of multi-material compliant mechanisms in which the algorithm ultimately designs both the topology of the part and the placement of each material – one stiff, one more compliant. Results – obtained through development of a both a new multi-material model and through development of a robust topology
optimization technique for the elimination of one-node hinges – show the ability to place both soft and stiff material and lead to dramatic improvements in performance of compliant mechanisms. One of the manufacturing challenges in metal powder-based 3D printing technologies is material curling due to
internal stress development from the heating and cooling cycle during the printing process. To counteract this phenomena, sacrificial support material is introduced to anchor the part to the build plate, which must then be removed chemically or mechanically in post-production: a time consuming process. Components requiring no post-printing material removal are achieved through development of a topology
optimization algorithm to design components to respect a designer-prescribed maximum overhang angle, such that the optimized part can be manufactured without using sacrificial support anchors. Solutions are shown to satisfy the prescribed overhang constraint, along with minimum feature length scale constraints as needed. Finally, an algorithm is developed considering the ability to embed discrete objects such as stiffeners or actuators within a monolithic printed part. Herein, a hybrid continuum-truss topology
optimization algorithm is developed to leverage this potential capability,
where the algorithm designs not only the continuum phase, but also places discrete truss members within…
Advisors/Committee Members: Guest, James K (advisor).
Subjects/Keywords: Topology Optimization;
Structural Optimization;
Additive Manufacturing;
3D Printing
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gaynor, A. T. (2015). Topology Optimization Algorithms for Additive Manufacturing. (Thesis). Johns Hopkins University. Retrieved from http://jhir.library.jhu.edu/handle/1774.2/38009
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Gaynor, Andrew Thomas. “Topology Optimization Algorithms for Additive Manufacturing.” 2015. Thesis, Johns Hopkins University. Accessed March 07, 2021.
http://jhir.library.jhu.edu/handle/1774.2/38009.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Gaynor, Andrew Thomas. “Topology Optimization Algorithms for Additive Manufacturing.” 2015. Web. 07 Mar 2021.
Vancouver:
Gaynor AT. Topology Optimization Algorithms for Additive Manufacturing. [Internet] [Thesis]. Johns Hopkins University; 2015. [cited 2021 Mar 07].
Available from: http://jhir.library.jhu.edu/handle/1774.2/38009.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Gaynor AT. Topology Optimization Algorithms for Additive Manufacturing. [Thesis]. Johns Hopkins University; 2015. Available from: http://jhir.library.jhu.edu/handle/1774.2/38009
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology
23.
van Tilburg, Alex (author).
Shape optimisation of a second skin: What can be achieved - in terms of structural and building physics performance - when an existing skin of a building is removed and replaced by a new facade.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:9942a688-f8bb-4c94-8cda-8ea98d87989f
► To reach the European Union climate targets of 2020 the rate of refurbishment must increase. The problem is that there are many barriers to refurbishment,…
(more)
▼ To reach the European Union climate targets of 2020 the rate of refurbishment must increase. The problem is that there are many barriers to refurbishment, which causes a low rate and low quality. The objective is to overcome these barriers and stimulate facade refurbishment. This thesis looks at the improvement, that can be made when replacing an existing skin by a new facade focusing on improving the structural efficiency and touch upon building physics. The main driving forces of this thesis are parametric design and optimisation. A parametric design is crucial for this thesis to perform a variation study. Different shapes of the facade are simulated with a custom made genetic algorithm to optimise the shape of the facade. First of all, the cost can be influenced by minimising the amount of material by altering: cross-sections, beam distances, etc. Secondly, by changing the shape of the facade a more aerodynamic building can be created. When the curvature increases, the wind load can be reduced which can make the structure more efficient. The wind load on the facade is determined with the computational fluid dynamics (CFD). The part about building physics focusses on ventilation. A ventilation system is designed which emphasises the importance of integrating the ventilation system with the second skin. The design builds upon the results of the CFD simulation and the structural model. The performance of the system is quantified by determining the usage of natural resources.
Civil Engineering | Building Engineering
Advisors/Committee Members: Nijsse, Rob (mentor), van der Linden, Lennert (graduation committee), Bristogianni, Telesilla (graduation committee), van der Spoel, Willem (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: parametric design; structural optimization; shape optimization; natural ventilation; optimisation
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
van Tilburg, A. (. (2019). Shape optimisation of a second skin: What can be achieved - in terms of structural and building physics performance - when an existing skin of a building is removed and replaced by a new facade. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:9942a688-f8bb-4c94-8cda-8ea98d87989f
Chicago Manual of Style (16th Edition):
van Tilburg, Alex (author). “Shape optimisation of a second skin: What can be achieved - in terms of structural and building physics performance - when an existing skin of a building is removed and replaced by a new facade.” 2019. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:9942a688-f8bb-4c94-8cda-8ea98d87989f.
MLA Handbook (7th Edition):
van Tilburg, Alex (author). “Shape optimisation of a second skin: What can be achieved - in terms of structural and building physics performance - when an existing skin of a building is removed and replaced by a new facade.” 2019. Web. 07 Mar 2021.
Vancouver:
van Tilburg A(. Shape optimisation of a second skin: What can be achieved - in terms of structural and building physics performance - when an existing skin of a building is removed and replaced by a new facade. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:9942a688-f8bb-4c94-8cda-8ea98d87989f.
Council of Science Editors:
van Tilburg A(. Shape optimisation of a second skin: What can be achieved - in terms of structural and building physics performance - when an existing skin of a building is removed and replaced by a new facade. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:9942a688-f8bb-4c94-8cda-8ea98d87989f

Delft University of Technology
24.
Huijgen, Rolf (author).
The Knowledge Factory.
Degree: 2018, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:64274d1a-867b-4ca3-950f-f8f8c04e6488
► The amount of startups in the Netherlands is growing, but yet the likelihood of a startup succeeding remains the same. Startup Incubators tremendously increase the…
(more)
▼ The amount of startups in the Netherlands is growing, but yet the likelihood of a startup succeeding remains the same. Startup Incubators tremendously increase the startups odds of surviving by training them the ins and outs of starting a business. Proper networking, sharing experience or sharing knowledge if you will is a crucial aspect that the startups have to learn to survive. This process of sharing between users can be positively affected by the space they reside in. The knowledge factory optimizes the sharing process by looking at both the physical (programmatic) and the mental (healthy working environment) requirements. The mental process has been addressed by using principles coming from cognitive architecture. Looking at human behavior on a subconscious level and try to use these principles to ‘control’ the inhabitants into taking better care of their physical and mental wellbeing. In addition, the growth or decline of startups is very unstable. The Knowledge Factory copes with this uncertainty by allowing the startups to also physically grow within the building.
Advisors/Committee Members: Bier, Henriette (mentor), Mostafavi, Sina (graduation committee), Adema, Ferry (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Start-up; Cognitive architecture; Structural Optimization; Daylight optimization; Rheothomic surfaces
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Huijgen, R. (. (2018). The Knowledge Factory. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:64274d1a-867b-4ca3-950f-f8f8c04e6488
Chicago Manual of Style (16th Edition):
Huijgen, Rolf (author). “The Knowledge Factory.” 2018. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:64274d1a-867b-4ca3-950f-f8f8c04e6488.
MLA Handbook (7th Edition):
Huijgen, Rolf (author). “The Knowledge Factory.” 2018. Web. 07 Mar 2021.
Vancouver:
Huijgen R(. The Knowledge Factory. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:64274d1a-867b-4ca3-950f-f8f8c04e6488.
Council of Science Editors:
Huijgen R(. The Knowledge Factory. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:64274d1a-867b-4ca3-950f-f8f8c04e6488

University of Maryland
25.
Middha, Parteek.
Seismic Design Optimization of Steel Structures Using Particle Swarm Algorithm.
Degree: Civil Engineering, 2017, University of Maryland
URL: http://hdl.handle.net/1903/20454
► Earthquakes are one of the most devastating and expensive natural disasters in the world. Economical and earthquake-resistant design remains a challenge for structural engineers. This…
(more)
▼ Earthquakes are one of the most devastating and expensive natural disasters in the world. Economical and earthquake-resistant design remains a challenge for
structural engineers. This study explores the optimal design of a seismic force resisting steel frame using a population based stochastic algorithm known as Particle Swarm
Optimization (PSO). PSO is able to efficiently explore a complex solution space with many design variables and constraints. PSO is also problem independent and can be built around any approach to earthquake design. As a case study, the seismic design of a three-story moment resisting frame is optimized for the linear static, linear dynamic, and nonlinear static analysis methods. An interface was created between MATLAB and OpenSees to link
optimization with a well-known and freely available earthquake engineering software. This application is extended to the performance-based design of structures, in which the optimal design meets the target performance objectives of Immediate Occupancy, Life Safety, and Collapse Prevention under Frequent, Design, and Maximum-considered seismic hazard levels.
Advisors/Committee Members: Phillips, Brian M (advisor).
Subjects/Keywords: Civil engineering; Metaheuristic Optimization; OpenSees-MATLAB; Particle Swarm Optimization; Performance-Based Design Optimization; Seismic Design Optimization; Structural Design Optimization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Middha, P. (2017). Seismic Design Optimization of Steel Structures Using Particle Swarm Algorithm. (Thesis). University of Maryland. Retrieved from http://hdl.handle.net/1903/20454
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Middha, Parteek. “Seismic Design Optimization of Steel Structures Using Particle Swarm Algorithm.” 2017. Thesis, University of Maryland. Accessed March 07, 2021.
http://hdl.handle.net/1903/20454.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Middha, Parteek. “Seismic Design Optimization of Steel Structures Using Particle Swarm Algorithm.” 2017. Web. 07 Mar 2021.
Vancouver:
Middha P. Seismic Design Optimization of Steel Structures Using Particle Swarm Algorithm. [Internet] [Thesis]. University of Maryland; 2017. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/1903/20454.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Middha P. Seismic Design Optimization of Steel Structures Using Particle Swarm Algorithm. [Thesis]. University of Maryland; 2017. Available from: http://hdl.handle.net/1903/20454
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology
26.
Vergeer, Michael (author).
Structural topology optimization of an active motion compensated gangway.
Degree: 2018, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:ab92c1fb-a5b1-4302-b2b4-fcd36b84f0dc
► In the offshore industry, there is a growing demand for designing efficient, sustainable and competitive products. In order to fulfil the component requirements, a method…
(more)
▼ In the offshore industry, there is a growing demand for designing efficient, sustainable and competitive products. In order to fulfil the component requirements, a method named topology
optimization can be applied. This is a mathematical design method which can be used in the early phases of the design process.At IHC there is an interest of applying topology
optimization for their equipment development process. Therefore the possibilities and limitations of the method should be investigated thoroughly. The research covers the
optimization process of a motion compensated gangway. A motion compensated gangway is a walkway which can be used to provide access from the transport vessel to the offshore structure. Its function is to transport people and cargo safely from the ship to the offshore structure or vice versa. The goal of this research was to determine to what extent topology
optimization can be used in the design of a motion compensated gangway. Finding an optimized result in terms of weight and stiffness by using this mathematical method which satisfies all the requirements. The
structural optimization is carried out with several commercial software packages which are compared by using a multi-criteria analysis. During the
optimization process it has been found that there are essentially two stages in the
optimization process. In the first stage, the topology or beam orientation of the structure is defined by the topology
optimization process. In this part the concept of the design is generated. Variation of the
optimization parameters was used in order to develop an efficient structure. The objective for the optimizer was to minimize the compliance of the structure for a certain volume fraction. In the second stage, the dimensions of all the beams and elements are defined by performing a size
optimization. A line model is generated which represents the orientation of the members in the structure. During the size
optimization the shape and the dimensions of the members are defined in order to fulfill the objective. The objective is to minimize the mass of the structure while constraints are defined for the maximum allowable stresses in the members and the maximum vertical deflection of the structure. This post-processing step is required in order to obtain a feasible design. The
structural stability of the gangway was improved by performing a linear buckling analysis and by adapting the structure in order to reduce the buckling behaviour. In the final step of the
optimization process, a CAD drawing is generated. This model is analysed by performing a finite element analysis. This showed that the new optimized design satisfies all the requirements which are stated by the DNV for designing a motion compensated gangway. The combination of the topology and size
optimization resulted in a new design which yielded a weight reduction of 36,4% compared to the current design. The weight was reduced from 13,08 ton to 8,31 ton, while still satisfying all the constraints.…
Advisors/Committee Members: Miedema, Sape (graduation committee), Langelaar, Matthijs (graduation committee), Helmons, Rudy (graduation committee), Kromwijk, PJ (mentor), Delft University of Technology (degree granting institution).
Subjects/Keywords: Optimization; Topology optimization; Shape optimization; Motion compensated gangway; Structural Optimization; Optistruct; Hyperworks; Size optimization; Design methodology
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Vergeer, M. (. (2018). Structural topology optimization of an active motion compensated gangway. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:ab92c1fb-a5b1-4302-b2b4-fcd36b84f0dc
Chicago Manual of Style (16th Edition):
Vergeer, Michael (author). “Structural topology optimization of an active motion compensated gangway.” 2018. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:ab92c1fb-a5b1-4302-b2b4-fcd36b84f0dc.
MLA Handbook (7th Edition):
Vergeer, Michael (author). “Structural topology optimization of an active motion compensated gangway.” 2018. Web. 07 Mar 2021.
Vancouver:
Vergeer M(. Structural topology optimization of an active motion compensated gangway. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:ab92c1fb-a5b1-4302-b2b4-fcd36b84f0dc.
Council of Science Editors:
Vergeer M(. Structural topology optimization of an active motion compensated gangway. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:ab92c1fb-a5b1-4302-b2b4-fcd36b84f0dc

Virginia Tech
27.
Locatelli, Davide.
Optimization of Supersonic Aircraft Wing-Box using Curvilinear SpaRibs.
Degree: PhD, Engineering Science and Mechanics, 2012, Virginia Tech
URL: http://hdl.handle.net/10919/26345
► This dissertation investigates the advantages of using curvilinear spars and ribs, termed SpaRibs, to design supersonic aircraft wing-box in comparison to the use of classic…
(more)
▼ This dissertation investigates the advantages of using curvilinear spars and ribs, termed SpaRibs, to design supersonic aircraft wing-box in comparison to the use of classic design concepts that employ straight spars and ribs. The intent is to achieve a more efficient load-bearing mechanism and to passively control aeorelastic behavior of the structure under the flight loads. The use of SpaRibs broadens the design space and allows for the natural frequencies and natural mode shape tailoring.
The SpaRibs concept is implemented in a new MATLAB-based
optimization framework referred to as EBF3SSWingOpt. This framework interfaces different analysis software to perform the tasks required. VisualDOC is used as optimizer; the generation of the SpaRibs geometry and of the structure Finite Element Model (FEM) is performed by MD.PATRAN; MD.NASTRAN is utilized to compute the weight of the structure, the linear static stress analysis and the linear buckling analysis required for the calculation of the response functions. EBF3SSWingOpt
optimization scheme performs both the sizing and the shaping of the internal
structural elements. Two methods are compared while optimizing the wing-box; a One-Step method in which sizing and topology
optimization are carried out simultaneously and a Two-Step method, in which the sizing and topology
optimization are carried out separately but in an iterative way. The
optimization problem statements for the One-Step and the Two-Step methodologies are presented.
Three methods to define the shape of the SpaRibs parametrically are described: (1) the Bounding Box and Base Curves method defines the shape of the SpaRibs based on the shape of two curves called Base Curves which are positioned into the Bounding Box, a rectangular region defined on the plane z=0 and containing the projection of the wing plan-form onto the same plane; (2) the Linked Shape method defines the shape of a set of SpaRibs in a one by one square domain of the natural space. The set of curves is subsequently transformed in the physical space for creating the wing structure geometry layout. The shape of each curve of each set is unique however, mathematical relations link their curvature in an effort to reduce the number of design variables; and (3) the Independent Shape parameterization is similar to the Linked Shape parameterization however, the shape of each curve is unique.
The framework and parameterization methods described are applied to optimize different types of wing structures. Following results are presented and discussed: (1) a rectangular wing-box subjected to a chord-wise linearly varying load, optimized using SpaRibs parameterized with Bounding-Box and Base Curves method; (2) a rectangular wing-box subjected to a chord-wise linearly varying load, optimized using SpaRibs parameterized with Linked Shape method; (3) a generic fighter wing subjected to uniform distributed pressure load, optimized using SpaRibs parameterized with Bounding-Box and Base Curves method; (4) a general business jet wing subjected to pull-up…
Advisors/Committee Members: Kapania, Rakesh K. (committeechair), Singh, Mahendra P. (committee member), Patil, Mayuresh J. (committee member), Thangjitham, Surot (committee member), Schetz, Joseph A. (committee member).
Subjects/Keywords: Structural Optimization; Wing Optimization; SpaRibs; Aircraft Design; Particle Swarm Optimization; Supersonic Aircraft Design
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Locatelli, D. (2012). Optimization of Supersonic Aircraft Wing-Box using Curvilinear SpaRibs. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/26345
Chicago Manual of Style (16th Edition):
Locatelli, Davide. “Optimization of Supersonic Aircraft Wing-Box using Curvilinear SpaRibs.” 2012. Doctoral Dissertation, Virginia Tech. Accessed March 07, 2021.
http://hdl.handle.net/10919/26345.
MLA Handbook (7th Edition):
Locatelli, Davide. “Optimization of Supersonic Aircraft Wing-Box using Curvilinear SpaRibs.” 2012. Web. 07 Mar 2021.
Vancouver:
Locatelli D. Optimization of Supersonic Aircraft Wing-Box using Curvilinear SpaRibs. [Internet] [Doctoral dissertation]. Virginia Tech; 2012. [cited 2021 Mar 07].
Available from: http://hdl.handle.net/10919/26345.
Council of Science Editors:
Locatelli D. Optimization of Supersonic Aircraft Wing-Box using Curvilinear SpaRibs. [Doctoral Dissertation]. Virginia Tech; 2012. Available from: http://hdl.handle.net/10919/26345

Lehigh University
28.
Saydam, Duygu.
Reliability and Risk of Structural Systems under Progressive and Sudden Damage.
Degree: PhD, Structural Engineering, 2013, Lehigh University
URL: https://preserve.lehigh.edu/etd/1616
► Structural systems are usually subjected to progressive and/or sudden damage throughout their lifetime. Damage can cause a reduced level of safety and increase the life-cycle…
(more)
▼ Structural systems are usually subjected to progressive and/or sudden damage throughout their lifetime. Damage can cause a reduced level of safety and increase the life-cycle cost. In order to keep the safety and proper functionality of structures above prescribed thresholds, maintenance interventions should be well planned. Informed decision making for maintaining the required safety and serviceability levels of
structural systems under uncertainty during their lifetime can only be achieved through integrated life-cycle management planning.
Structural performance assessment and prediction,
optimization of inspection and monitoring activities, updating the performance with information from inspection and monitoring,
optimization of maintenance and repair activities and decision making are the main tasks of an integrated life-cycle management framework. Accurate prediction and quantification of life-cycle performance is the most critical task in a life-cycle management framework. Uncertainty is inevitable in all aspects of this framework. Aggressive environmental conditions may cause the strength of a structure to deteriorate progressively in time. The deterioration process is complex and contains high uncertainty. Therefore, probabilistic methods are required for accurate assessment of
structural performance. Reliability-based performance measures are the primary tool for
structural management
optimization frameworks. Extreme events such as floods, earthquakes, and blasts may cause sudden damage to structures. A structure must be able to withstand local damage without experiencing disproportionate consequences. Performance measures such as reliability, redundancy, robustness, vulnerability and damage tolerance should be considered in the life-cycle management of structures. Risk-based approaches provide the means of combining the probability of
structural failure with the consequences of this event. There is the need to effectively incorporate the risk-based performance measures into the life-cycle management frameworks by accounting for the probabilities of occurrence of failure events and the associated consequences using scenario-based approaches in a computationally efficient manner. The main objective of this study is to develop means for integrating the reliability-based and risk-based performance indicators in a life-cycle management framework for structures undergoing progressive and sudden damage. An approach for quantifying time-variant reliability, redundancy, vulnerability, and robustness of
structural systems in a life-cycle context is developed. A methodology for quantifying lifetime risk associated with the component failure and risk-based robustness of bridge superstructures is proposed. Furthermore, a risk-based maintenance
optimization methodology for deteriorating bridges to establish optimum maintenance plans is proposed. A methodology to assess the time-dependent expected losses and risk-based robustness of highway bridge networks consisting of deteriorating bridges is established. In addition, a…
Advisors/Committee Members: Frangopol, Dan M..
Subjects/Keywords: life-cycle performance; performance indicators; risk; structural damage; structural optimization; structural reliability; Civil and Environmental Engineering; Engineering; Structural Engineering
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Saydam, D. (2013). Reliability and Risk of Structural Systems under Progressive and Sudden Damage. (Doctoral Dissertation). Lehigh University. Retrieved from https://preserve.lehigh.edu/etd/1616
Chicago Manual of Style (16th Edition):
Saydam, Duygu. “Reliability and Risk of Structural Systems under Progressive and Sudden Damage.” 2013. Doctoral Dissertation, Lehigh University. Accessed March 07, 2021.
https://preserve.lehigh.edu/etd/1616.
MLA Handbook (7th Edition):
Saydam, Duygu. “Reliability and Risk of Structural Systems under Progressive and Sudden Damage.” 2013. Web. 07 Mar 2021.
Vancouver:
Saydam D. Reliability and Risk of Structural Systems under Progressive and Sudden Damage. [Internet] [Doctoral dissertation]. Lehigh University; 2013. [cited 2021 Mar 07].
Available from: https://preserve.lehigh.edu/etd/1616.
Council of Science Editors:
Saydam D. Reliability and Risk of Structural Systems under Progressive and Sudden Damage. [Doctoral Dissertation]. Lehigh University; 2013. Available from: https://preserve.lehigh.edu/etd/1616

Delft University of Technology
29.
To, Tony (author).
Structural optimization of modular high-rise buildings.
Degree: 2020, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:285cc1d6-5463-4da5-a35a-edeb14448c4e
► <p class="MsoNormal">The demand for high-rise building has been increasing over the past decades which has induced new developments such as modular construction. Modular construction has…
(more)
▼ <p class="MsoNormal">The demand for high-rise building has been increasing over the past decades which has induced new developments such as modular construction. Modular construction has advantages in terms increased speed, safer construction and less construction waste. Applying modular construction in high-rise however brings about great complexities for the structural design of the building. Therefore, a design aid is created which generates a structural model from any arbitrary shape and uses structural optimization techniques to explore a range of designs for the early design stage. Existing optimization techniques have been studied, including Cross-Section (CS-) optimization (size) and BESO (topology). CS-optimization adapts the size of each member, considering utilization and displacement conditions whereas BESO removes or adds elements from the model based on stress level and Target Ratio (TR). Performing the methods successively further decreases the structural weight at certain TR. Generally, weight increases as more elements are removed. By developing the two-way coupled ESO<>CS-optimization method, elements are removed by lowest strain energy density, while the cross-sections of the remaining members are updated in each iteration, thus coupling ESO (topology) and CS-optimization (size). This results in a logical load path and additional weight reduction especially in the braced frame structures loaded by lateral loads when displacement is governing. In multiple load case design, the removal of elements is somewhat hard to interpret, however the method consistently results in the lowest structural weight for the considered cases. In order to create a modular structural design, boundary conditions are assumed by standardizing column and beam dimensions and considering multiple realistic load cases (wind+vertical load). By transforming arbitrary shapes into structural models and optimizing these, a range of solutions for the structural design is presented in which the number of elements and the structural weight are generally negatively related. For the considered rectangular buildings, the results are more efficient than core or outrigger structures and almost as efficient as mega frame structures, with the added benefit that it can be applied to any shape. Exploration of these solutions is a useful contribution to the early design stage of modular high-rise buildings, while the coupled ESO<>CS-optimization method could also be useful in other optimization problems.
Civil Engineering | Building Engineering - Structural Design
Advisors/Committee Members: Hendriks, Max (mentor), Crielaard, Roy (mentor), van der Linden, Lennert (mentor), Lukovic, Mladena (mentor), Delft University of Technology (degree granting institution).
Subjects/Keywords: Structural optimization; Topology optimization; Size optimization; High-rise buildings; Modular construction; Parametric design; Karamba3D; BESO; ESO; Cross-section optimization
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
To, T. (. (2020). Structural optimization of modular high-rise buildings. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:285cc1d6-5463-4da5-a35a-edeb14448c4e
Chicago Manual of Style (16th Edition):
To, Tony (author). “Structural optimization of modular high-rise buildings.” 2020. Masters Thesis, Delft University of Technology. Accessed March 07, 2021.
http://resolver.tudelft.nl/uuid:285cc1d6-5463-4da5-a35a-edeb14448c4e.
MLA Handbook (7th Edition):
To, Tony (author). “Structural optimization of modular high-rise buildings.” 2020. Web. 07 Mar 2021.
Vancouver:
To T(. Structural optimization of modular high-rise buildings. [Internet] [Masters thesis]. Delft University of Technology; 2020. [cited 2021 Mar 07].
Available from: http://resolver.tudelft.nl/uuid:285cc1d6-5463-4da5-a35a-edeb14448c4e.
Council of Science Editors:
To T(. Structural optimization of modular high-rise buildings. [Masters Thesis]. Delft University of Technology; 2020. Available from: http://resolver.tudelft.nl/uuid:285cc1d6-5463-4da5-a35a-edeb14448c4e
30.
JoÃo Baptista Cardoso Athayde Lima.
ContribuiÃÃes para otimizaÃÃo estrutural de torres tubulares de aÃo para turbinas eÃlicas.
Degree: Master, 2011, Universidade Federal do Ceará
URL: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8131
;
► As grandes questÃes do mundo globalizado tÃm passado, necessariamente, pelos temas ligados à sustentabilidade, energia limpa, exploraÃÃo do meio ambiente de forma ecologicamente correta e…
(more)
▼ As grandes questÃes do mundo globalizado tÃm passado, necessariamente, pelos temas ligados à sustentabilidade, energia limpa, exploraÃÃo do meio ambiente de forma ecologicamente correta e inovaÃÃo tecnolÃgica para manter o planeta saudÃvel. Nesse contexto, a energia eÃlica vem se destacando, principalmente na regiÃo Nordeste do Brasil, pelo grande potencial dos ventos e as caracterÃsticas de renovabilidade e complementaridade com a energia das hidrelÃtricas. As torres, que representam parcela significativa do custo do sistema, tendem a crescer buscando ventos com maiores velocidade e permitindo a utilizaÃÃo de turbinas eÃlicas de maior capacidade de geraÃÃo, acentuando-se a sua importÃncia como elemento estrutural do sistema. O objetivo geral deste trabalho à formular um modelo de otimizaÃÃo de torres tubulares de aÃo, composta de segmentos em tronco de cone. Busca-se a soluÃÃo de peso mÃnimo, tendo como variÃveis de projeto os diÃmetros externos e as espessuras de chapa caracterÃsticas de cada segmento. RestriÃÃes relativas à resistÃncia, à estabilidade e rigidez sÃo impostas com base em normas brasileiras. RestriÃÃes relativas à frequÃncia natural, a limitaÃÃes de transporte e geomÃtricas sÃo tambÃm requeridas. O conjunto nacele/rotor à modelado como uma massa rÃgida fixada no topo da torre, sem rotaÃÃo, e o carregamento atuante na estrutura inclui os pesos da torre e do conjunto rotor/nacele, o efeito estÃtico da aÃÃo do vento sobre a torre e as pÃs do rotor. A concepÃÃo de anÃlise adota modelo de viga engastada na base e livre no topo e emprega uma formulaÃÃo nÃo linear geomÃtrica pelo MÃtodo de Elementos finitos usando um programa em C++. O modelo de otimizaÃÃo foi implementado no MATLAB e, devido à natureza discreta das variÃveis de projeto e Ãs descontinuidades de funÃÃes de restriÃÃo e de suas derivadas, utilizam-se algoritmos genÃticos na soluÃÃo. Buscas na vizinhanÃa das soluÃÃes discretas sÃo realizadas usando um algoritmo baseado em informaÃÃo de gradiente (fmincon do MATLAB). AplicaÃÃes para vÃrias alturas de torre sÃo feitas, incluindo comparaÃÃes com uma torre cilÃndrica para validaÃÃo do modelo. Os resultados sÃo analisados frente aos de outros modelos da literatura. Os conceitos de projeto de torre rÃgida e flexÃvel sÃo discutidos relaxando-se as restriÃÃes de rigidez e de frequÃncia. SoluÃÃes obtidas sÃo analisadas usando elementos de casca do programa de anÃlise ABAQUS para verificaÃÃo de tensÃes e deslocamentos
The main subjects of the globalized world have passed necessarily by issues related to sustainability, clean energy, environment exploration in an ecologically correct way, and technology innovation to maintain a healthy planet. In this context, the wind has been highlighting, especially in the Northeast of Brazil, because of the large wind potential and the characteristics of renewability and complementarily with hydropower energy. The towers represent significant portion of the cost of the system, tends to grow seeking greatest wind speeds and allowing the use of wind turbines with…
Advisors/Committee Members: AntÃnio MacÃrio Cartaxo de Melo.
Subjects/Keywords: ENGENHARIA CIVIL; Engenharia Estrutural; Estruturas de aÃo; OtimizaÃÃo estrutural; Structural Engineering; Steel Structures; Structural Optimization
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❌
APA ·
Chicago ·
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Vancouver ·
CSE |
Export
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Manager
APA (6th Edition):
Lima, J. B. C. A. (2011). ContribuiÃÃes para otimizaÃÃo estrutural de torres tubulares de aÃo para turbinas eÃlicas. (Masters Thesis). Universidade Federal do Ceará. Retrieved from http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8131 ;
Chicago Manual of Style (16th Edition):
Lima, JoÃo Baptista Cardoso Athayde. “ContribuiÃÃes para otimizaÃÃo estrutural de torres tubulares de aÃo para turbinas eÃlicas.” 2011. Masters Thesis, Universidade Federal do Ceará. Accessed March 07, 2021.
http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8131 ;.
MLA Handbook (7th Edition):
Lima, JoÃo Baptista Cardoso Athayde. “ContribuiÃÃes para otimizaÃÃo estrutural de torres tubulares de aÃo para turbinas eÃlicas.” 2011. Web. 07 Mar 2021.
Vancouver:
Lima JBCA. ContribuiÃÃes para otimizaÃÃo estrutural de torres tubulares de aÃo para turbinas eÃlicas. [Internet] [Masters thesis]. Universidade Federal do Ceará 2011. [cited 2021 Mar 07].
Available from: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8131 ;.
Council of Science Editors:
Lima JBCA. ContribuiÃÃes para otimizaÃÃo estrutural de torres tubulares de aÃo para turbinas eÃlicas. [Masters Thesis]. Universidade Federal do Ceará 2011. Available from: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8131 ;
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