subject:(granular material)

Texas A&M University

1. Gu, Fan. Characterization and Performance Prediction of Unbound Granular Bases with and Without Geogrids in Flexible Pavements.

Degree: PhD, Civil Engineering, 2015, Texas A&M University

URL: http://hdl.handle.net/1969.1/156410

► Unbound granular materials (UGMs) constitute the supporting layer of flexible pavements. The performance of unbound granular base layer has been widely recognized to be influenced… (more)

▼ Unbound granular materials (UGMs) constitute the supporting layer of flexible pavements. The performance of unbound granular base layer has been widely recognized to be influenced by its resilient modulus and permanent deformation, as well as whether it is reinforced by geogrids. The UGMs are found to exhibit moisture-sensitive and stress-dependent nonlinear cross-anisotropic behaviors, but are not adequately characterized by existing models in pavement engineering. The primary objective of this study is to develop a comprehensive methodology to accurately characterize the constitutive behavior of UGM, and predicting the performance of UGM in flexible pavements. Furthermore, this study aims at quantifying the influence of geogrid on pavement performance to facilitate the incorporation of geogrid into Pavement ME Design Software. A new resilient modulus model is first developed to characterize the moisture-sensitive and stress-dependent nonlinear cross-anisotropic behavior for UGM. The moisture dependence of UGM is characterized by the degree of saturation and the matric suction. This model is validated by the laboratory resilient modulus tests on the selected UGMs at different moisture contents. The finite element approach is then employed to predict the performance of flexible pavements by incorporating this constitutive model for UGM. To accurately predict the rutting depth of base course, a new mechanistic-empirical rutting model is also developed to forecast the rutting behavior of UGM at different stress levels. In this study, the repeated load triaxial tests are performed on a variety of granular materials to determine the resilient modulus and permanent deformation properties. The measured resilient modulus and permanent deformation properties are statistically related to a wide variety of performance-related base course properties. These regression models can accurately and efficiently predict the resilient modulus and permanent deformation properties of UGM. A laboratory methodology is developed to evaluate the impact of geogrid on cross-anisotropy and permanent deformation properties of UGM. This impact is successfully predicted by an analytical model. Finite element models are developed to simulate the geogrid-reinforced structures by considering the geogrid-reinforcement mechanisms. These numerical models are validated by the large-scale tank tests. The validated finite element models provide a sound basis for predicting the performance of geogrid-reinforced pavements. Advisors/Committee Members: Lytton, Robert L (advisor), Luo, Rong (advisor), Epps, Jon A (committee member), Kinra, Vikram (committee member), Park, Philip (committee member).

Subjects/Keywords: Geogrid; Granular Material; Flexible Pavement

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APA (6^th Edition):

Gu, F. (2015). Characterization and Performance Prediction of Unbound Granular Bases with and Without Geogrids in Flexible Pavements. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/156410

Chicago Manual of Style (16^th Edition):

Gu, Fan. “Characterization and Performance Prediction of Unbound Granular Bases with and Without Geogrids in Flexible Pavements.” 2015. Doctoral Dissertation, Texas A&M University. Accessed April 13, 2021. http://hdl.handle.net/1969.1/156410.

MLA Handbook (7^th Edition):

Gu, Fan. “Characterization and Performance Prediction of Unbound Granular Bases with and Without Geogrids in Flexible Pavements.” 2015. Web. 13 Apr 2021.

Vancouver:

Gu F. Characterization and Performance Prediction of Unbound Granular Bases with and Without Geogrids in Flexible Pavements. [Internet] [Doctoral dissertation]. Texas A&M University; 2015. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1969.1/156410.

Council of Science Editors:

Gu F. Characterization and Performance Prediction of Unbound Granular Bases with and Without Geogrids in Flexible Pavements. [Doctoral Dissertation]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/156410

University of Sydney

2. Marks, Benjamin. Grainsize dynamics of granular flows .

Degree: 2013, University of Sydney

URL: http://hdl.handle.net/2123/9372

► This dissertation deals with the description of a granular material as a continuum with an internal coordinate that represents the grainsize distribution. The inclusion of… (more)

Subjects/Keywords: Granular material; Geomechanics; Granular flow; Landslides; Avalanches; Segregation

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APA (6^th Edition):

Marks, B. (2013). Grainsize dynamics of granular flows . (Thesis). University of Sydney. Retrieved from http://hdl.handle.net/2123/9372

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Marks, Benjamin. “Grainsize dynamics of granular flows .” 2013. Thesis, University of Sydney. Accessed April 13, 2021. http://hdl.handle.net/2123/9372.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Marks, Benjamin. “Grainsize dynamics of granular flows .” 2013. Web. 13 Apr 2021.

Vancouver:

Marks B. Grainsize dynamics of granular flows . [Internet] [Thesis]. University of Sydney; 2013. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/2123/9372.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Marks B. Grainsize dynamics of granular flows . [Thesis]. University of Sydney; 2013. Available from: http://hdl.handle.net/2123/9372

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Cornell University

3. Tan, Danielle. Sound From Sand.

Degree: PhD, Theoretical and Applied Mechanics, 2012, Cornell University

URL: http://hdl.handle.net/1813/29283

► Various methods of producing sound from 'sounding' sand in the laboratory are explored. Low amplitude sound with frequency similar to that of 'booming' during spontaneous… (more)

Subjects/Keywords: granular material; sound production; kinetic theory

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APA (6^th Edition):

Tan, D. (2012). Sound From Sand. (Doctoral Dissertation). Cornell University. Retrieved from http://hdl.handle.net/1813/29283

Chicago Manual of Style (16^th Edition):

Tan, Danielle. “Sound From Sand.” 2012. Doctoral Dissertation, Cornell University. Accessed April 13, 2021. http://hdl.handle.net/1813/29283.

MLA Handbook (7^th Edition):

Tan, Danielle. “Sound From Sand.” 2012. Web. 13 Apr 2021.

Vancouver:

Tan D. Sound From Sand. [Internet] [Doctoral dissertation]. Cornell University; 2012. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1813/29283.

Council of Science Editors:

Tan D. Sound From Sand. [Doctoral Dissertation]. Cornell University; 2012. Available from: http://hdl.handle.net/1813/29283

Georgia Tech

4. Gosyne, Jonathan R. Bipedal robotic walking on granular material: An inertial and kinematic control approach.

Degree: MS, Mechanical Engineering, 2018, Georgia Tech

URL: http://hdl.handle.net/1853/62246

► Bipedal robotic locomotion in granular media presents a unique set of challenges at the intersection of granular physics and robotic locomotion. In this project, we… (more)

Subjects/Keywords: Biped; Robotics; Granular material; Controls; Locomotion; Robophysics

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APA (6^th Edition):

Gosyne, J. R. (2018). Bipedal robotic walking on granular material: An inertial and kinematic control approach. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/62246

Chicago Manual of Style (16^th Edition):

Gosyne, Jonathan R. “Bipedal robotic walking on granular material: An inertial and kinematic control approach.” 2018. Masters Thesis, Georgia Tech. Accessed April 13, 2021. http://hdl.handle.net/1853/62246.

MLA Handbook (7^th Edition):

Gosyne, Jonathan R. “Bipedal robotic walking on granular material: An inertial and kinematic control approach.” 2018. Web. 13 Apr 2021.

Vancouver:

Gosyne JR. Bipedal robotic walking on granular material: An inertial and kinematic control approach. [Internet] [Masters thesis]. Georgia Tech; 2018. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1853/62246.

Council of Science Editors:

Gosyne JR. Bipedal robotic walking on granular material: An inertial and kinematic control approach. [Masters Thesis]. Georgia Tech; 2018. Available from: http://hdl.handle.net/1853/62246

Iowa State University

5. Ladd, Christopher R. An experimental analysis of force distribution in a two-phase system.

Degree: 2020, Iowa State University

URL: https://lib.dr.iastate.edu/etd/17912

► Two-phase systems, in which one phase is solid and the other fluid, are widespread in nature. Examples of such systems include reservoir rocks holding vital… (more)

▼ Two-phase systems, in which one phase is solid and the other fluid, are widespread in nature. Examples of such systems include reservoir rocks holding vital fluids like water or petroleum; slurries of partially crystallized magmas; the semi-brittle middle crust where, at the same pressure and temperature conditions, some minerals fracture in a brittle manner while others flow in a ductile manner; and fluids migrating along faults filled with fault gouge. Previous studies of two-phase systems have shown that they deform in a complex manner, where the weak phase plays an important role on deformation localization and dynamics. Here, I study the influence of a weak phase on stress distribution in a granular medium. To this end, in my experiments I deform a two-phase material in a simple shear apparatus under constant strain rate. I use photoelastic polyurethane discs as the granular or strong phase and a linear-viscous silicone as the weak phase. The photoelastic property of the discs allows for direct observation and measurement of force distributed throughout the system. I compare the two-phase experiments to granular experiments without the silicone. In the granular experiments I observe force chains, connected sequences of highly stressed discs, forming in a framework pattern oriented parallel to the principal stress direction. With the addition of the fluid, force initially localizes along the shear plane imposed by the experimental apparatus. The results show that the fluid phase can support force locally over an extended period of time. In contrast to the granular experiment, force chains can terminate within the experiment. The addition of the weak phase has a strong impact on the force distribution and the force chain orientation. In the two-phase system, the force chains form parallel to the shear plane and only rotate to the principal stress direction with an increase in strain. The experiments presented here quantify the impact of the weak phase in a granular system during deformation.

Subjects/Keywords: analog model; force chains; force distribution; granular material; two-phase material

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ladd, C. R. (2020). An experimental analysis of force distribution in a two-phase system. (Thesis). Iowa State University. Retrieved from https://lib.dr.iastate.edu/etd/17912

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ladd, Christopher R. “An experimental analysis of force distribution in a two-phase system.” 2020. Thesis, Iowa State University. Accessed April 13, 2021. https://lib.dr.iastate.edu/etd/17912.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ladd, Christopher R. “An experimental analysis of force distribution in a two-phase system.” 2020. Web. 13 Apr 2021.

Vancouver:

Ladd CR. An experimental analysis of force distribution in a two-phase system. [Internet] [Thesis]. Iowa State University; 2020. [cited 2021 Apr 13]. Available from: https://lib.dr.iastate.edu/etd/17912.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ladd CR. An experimental analysis of force distribution in a two-phase system. [Thesis]. Iowa State University; 2020. Available from: https://lib.dr.iastate.edu/etd/17912

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

6. Τσιάβος, Χρήστος. Μορφογένεση και οριακή ροή κοκκώδους υλικού σε δισδιάστατη κεκλιμένη πειραματική διάταξη.

Degree: 2009, University of Patras

URL: http://nemertes.lis.upatras.gr/jspui/handle/10889/1595

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Μελετάμε την ροή κοκκώδους σε κεκλιμένη πειραματική διάταξη δυο διαστάσεων, αποτελούμενη από Κ το πλήθος γραμμές και Μ το πλήθος στήλες δοχείων, τα οποία αναταράσσονται… (more)

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Μελετάμε την ροή κοκκώδους σε κεκλιμένη πειραματική διάταξη δυο διαστάσεων, αποτελούμενη από Κ το πλήθος γραμμές και Μ το πλήθος στήλες δοχείων, τα οποία αναταράσσονται κάθετα. Η ροή του υλικού από δοχείο σε δοχείο περιγράφεται από ένα μοντέλο ροής [Eggers, 1999; Van der Weele, 2008]. Υποκινούμενοι από δυσλειτουργίες που παρουσιάζονται στις σύγχρονες βιομηχανικές μονάδες μεταφοράς (όπως είναι ο σχηματισμός συσσωματωμάτων), εισάγουμε σταθερή ποσότητα υλικού στην πρώτη γραμμή των δοχείων, και καθορίζουμε τις συνθήκες κάτω από τις οποίες η ροή παραμένει ομαλή και συνεχής μέχρι την τελευταία γραμμή. Ενώ στην περίπτωση μιας και μόνο σειράς δοχείων (Μ=1) η εκροή μηδενίζεται με την εμφάνιση ενός και μόνο συσσωματώματος [Κανελλόπουλος, 2008], για Μ>1 απαιτούνται περισσότερα συσσωματώματα για τον μηδενισμό της. Μελετάμε τον τρόπο με τον οποίο αυτά τα συσσωματώματα διατάσσονται στα δοχεία, ο οποίος πολλές φορές όπως βλέπουμε μπορεί να είναι ιδιαίτερα πολύπλοκος, αποτελώντας έτσι ένα εξαίρετο παράδειγμα μορφογένεσης σε δυναμικά συστήματα [Cross and Hohenberg, 1993]. Εντοπίζουμε τα βασικά χαρακτηριστικά αυτής της μορφογένεσης και εξηγούμε πως αυτά σχετίζονται με το μοντέλο ροής. Για την περαιτέρω μαθηματική και φυσική τους ερμηνεία προτείνουμε το συνεχές όριο του μοντέλου ροής, το οποίο θα αποτελέσει την απαρχή για μελλοντικές έρευνες [Van der Weele et al, 2008]. Αναφορές: •J. Eggers, Sand as Maxwell’s demon, Phys. Rev. Lett. 83, 5322 (1999). •K. van der Weele, Granular gas dynamics: How Maxwell’s demon rules in a nonequilibrium system, Contemporary Phys. 49, 157-175 (2008). •Γ. Κανελλόπουλος, Οριακή ροή κοκκώδους υλικού σε διάδρομο μεταφοράς, Διπλωματική Εργασία, Τμήμα Μαθηματικών, Πανεπιστήμιο Πατρών (2008). •M.C. Cross and P.C. Hohenberg, Pattern formation outside of equilibrium, Rev.Mod.Phys. 65, 851 (1993). •K. van der Weele, G. Kanellopoulos, C. Tsiavos, and D. van der Meer, Transient granular shock waves and upstream motion on a staircase (submitted, 2009).

We study the dynamics of granular material in a 2-dimensional tilted setup, consisting of K rows and M columns of equal sized compartments, which is brought into motion by vertical shaking. Particles are inserted into the system along the upper row of compartments, then flow downwards, and eventually exit the system from the bottom row. Similar setups are encountered frequently in industrial transport machinery and are notorious for the tendency of the particles to form dense clusters, which obstruct the flow. We model the particle flow from box to box by a flux function and determine the maximal value of the inflow rate for which the flow remains steady. If the inflow rate exceeds this value, clusters are formed. The way in which these clusters are distributed over the KxM compartments is a fine example of spontaneous pattern formation. We analyze the main characteristics of this cluster formation, its dependence on the various parameters of the system, and its sensitivity to experimental fluctuations.

Advisors/Committee Members: Van der Weele, Jacob-Peter, Tsiavos, Christos, Van der Weele, Jacob-Peter, Καφούσιας, Νικόλαος, Μπούντης, Αναστάσιος.

Subjects/Keywords: Μορφογένεση; Κοκκώδης ροή; Κοκκώδη υλικά; 620.43; Pattern formation; Granular flow; Granular material

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APA (6^th Edition):

Τσιάβος, �. (2009). Μορφογένεση και οριακή ροή κοκκώδους υλικού σε δισδιάστατη κεκλιμένη πειραματική διάταξη. (Masters Thesis). University of Patras. Retrieved from http://nemertes.lis.upatras.gr/jspui/handle/10889/1595

Chicago Manual of Style (16^th Edition):

Τσιάβος, Χρήστος. “Μορφογένεση και οριακή ροή κοκκώδους υλικού σε δισδιάστατη κεκλιμένη πειραματική διάταξη.” 2009. Masters Thesis, University of Patras. Accessed April 13, 2021. http://nemertes.lis.upatras.gr/jspui/handle/10889/1595.

MLA Handbook (7^th Edition):

Τσιάβος, Χρήστος. “Μορφογένεση και οριακή ροή κοκκώδους υλικού σε δισδιάστατη κεκλιμένη πειραματική διάταξη.” 2009. Web. 13 Apr 2021.

Vancouver:

Τσιάβος �. Μορφογένεση και οριακή ροή κοκκώδους υλικού σε δισδιάστατη κεκλιμένη πειραματική διάταξη. [Internet] [Masters thesis]. University of Patras; 2009. [cited 2021 Apr 13]. Available from: http://nemertes.lis.upatras.gr/jspui/handle/10889/1595.

Council of Science Editors:

Τσιάβος �. Μορφογένεση και οριακή ροή κοκκώδους υλικού σε δισδιάστατη κεκλιμένη πειραματική διάταξη. [Masters Thesis]. University of Patras; 2009. Available from: http://nemertes.lis.upatras.gr/jspui/handle/10889/1595

Pontifical Catholic University of Rio de Janeiro

7. JOSE CARLOS LEITE DOS SANTOS. [en] A MATHEMATICAL FORMULATION OF THE THEORY OF GRANULAR MATERIALS.

Degree: 2018, Pontifical Catholic University of Rio de Janeiro

URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33274

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[pt] O propósito deste trabalho é propor um modelo teórico axiomático, que descreva o comportamento termomecânico de materiais granulares, fundamentado em uma descrição física simples,… (more)

Subjects/Keywords: [pt] MATERIAIS GRANULARES; [en] GRANULAR MATERIALS; [pt] COMPORTAMENTO TERMODINAMICO DE MATERIAIS GRANULARES; [en] THERMOMECHANICAL BEHAVIOR OF GRANULAR MATERIALS; [pt] ESCOAMENTO DE MATERIAL GRANULAR; [en] GRANULAR FLOW

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APA (6^th Edition):

SANTOS, J. C. L. D. (2018). [en] A MATHEMATICAL FORMULATION OF THE THEORY OF GRANULAR MATERIALS. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33274

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

SANTOS, JOSE CARLOS LEITE DOS. “[en] A MATHEMATICAL FORMULATION OF THE THEORY OF GRANULAR MATERIALS.” 2018. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed April 13, 2021. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33274.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

SANTOS, JOSE CARLOS LEITE DOS. “[en] A MATHEMATICAL FORMULATION OF THE THEORY OF GRANULAR MATERIALS.” 2018. Web. 13 Apr 2021.

Vancouver:

SANTOS JCLD. [en] A MATHEMATICAL FORMULATION OF THE THEORY OF GRANULAR MATERIALS. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2018. [cited 2021 Apr 13]. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33274.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

SANTOS JCLD. [en] A MATHEMATICAL FORMULATION OF THE THEORY OF GRANULAR MATERIALS. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2018. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33274

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Rochester

8. Wu, Yegang. Statistical properties of disordered jammed packings of frictionless disks.

Degree: PhD, 2016, University of Rochester

URL: http://hdl.handle.net/1802/30411

► We numerically simulate mechanically stable packings of soft-core, frictionless particles in two dimensions interacting with a short range contact potential for the purpose of studying… (more)

▼ We numerically simulate mechanically stable packings of soft-core, frictionless particles in two dimensions interacting with a short range contact potential for the purpose of studying the statistical properties in such disordered systems. To avoid crystallization of the particles, we use a mixture of equal numbers of big and small particles. To prepare a mechanically stable packing, we use the Conjugate Gradient Method to minimize the total energy of the system U(r) to its local minimum from randomly initialized particle positions. For our system with Lees-Edwards periodic boundary conditions, U implicitly depends on the box parameters (box length in x, y directions L_x, L_y and the skew ratio γ in the x direction). we define a modified total energy Ũ(r, L_x, L_y, γ) so that when Ũ is brought to its local minimum, not only the net force on each particle vanishes, but the total stress tensor of the system will simultaneously be the desired, isotropic stress tensor. We optimize our program so that an ensemble of configurations consisting of a large number of particles can be efficiently generated. Therefore we can have good accuracy on the statistics of the quantities that we want to measure. </br> We study a set of conserved quantities, in particular the stress Γ_C, the Maxwell-Cremona forcer-tile area A_C, the Voronoi volume V_C, the number of particles N_C, and the number of small particles N_sC on subclusters of particles C. These subclusters are sampled from non-overlapping clusters embedded in the systems with the fixed isotropic global system stress. We defined our circular subclusters in two ways; (i), clusters with fixed radius R; (ii), clusters with fixed number of particles M. We compute the averages, variances and correlations of the conserved quantities on the clusters. We find significantly different behavior of the conserved quantities for the two cluster ensembles. The cluster ensemble with fixed radius R has important advantages and is therefore selected for the study of stress distribution on clusters with the maximum entropy hypothesis. </br> We then show that the maximum entropy hypothesis can successfully explain the stress distribution on clusters for our system with isotropic total stress. In contrary to the previous claim that the stress alone as a conserved quantity is enough to explain the stress distribution on clusters, we find that an additional conserved quantity, called the Maxwell-Cremona force-tile area, also needs to be taken into consideration. We show that the joint distribution of the stress and force-tile area can be successfully explained by the maximum entropy hypothesis subject to constraints on the average values of the conserved quantities. </br> Finally, we investigate the fluctuation of local packing fraction ϕ(r) to test whether our configurations display the hyperuniformity that has beed claimed to exit exactly at ϕ_J. For our configurations with…

Subjects/Keywords: Frictionless; Granular material; Jammed; Maximum entropy hypothesis; Soft disk; Statistical property

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APA (6^th Edition):

Wu, Y. (2016). Statistical properties of disordered jammed packings of frictionless disks. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/30411

Chicago Manual of Style (16^th Edition):

Wu, Yegang. “Statistical properties of disordered jammed packings of frictionless disks.” 2016. Doctoral Dissertation, University of Rochester. Accessed April 13, 2021. http://hdl.handle.net/1802/30411.

MLA Handbook (7^th Edition):

Wu, Yegang. “Statistical properties of disordered jammed packings of frictionless disks.” 2016. Web. 13 Apr 2021.

Vancouver:

Wu Y. Statistical properties of disordered jammed packings of frictionless disks. [Internet] [Doctoral dissertation]. University of Rochester; 2016. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1802/30411.

Council of Science Editors:

Wu Y. Statistical properties of disordered jammed packings of frictionless disks. [Doctoral Dissertation]. University of Rochester; 2016. Available from: http://hdl.handle.net/1802/30411

Texas A&M University

9. Bernhardt, Michelle Lee. Examination of Granular Material Behavior in a Laminar-type Direct Simple Shear Device using Laboratory Validated Discrete Element Method Simulations.

Degree: PhD, Civil Engineering, 2013, Texas A&M University

URL: http://hdl.handle.net/1969.1/151646

► Simple shear testing is used to study a number of practical geotechnical problems including: soil conditions directly below a loaded surface, adjacent to a driven… (more)

▼ Simple shear testing is used to study a number of practical geotechnical problems including: soil conditions directly below a loaded surface, adjacent to a driven pile shaft, soils deposited on a slightly inclined slope, and most notably the response of soils subjected to earthquake-type loading. While each of these problems still have important questions to be answered, earthquakes and earthquake triggered geohazards are the most complex and also pose the highest risk. An important aspect of assessing the risk associated with earthquakes is the need to accurately predict soil behavior. True field loading conditions involve multidirectional shearing and the rotation of principal planes and are much more complex than the triaxial laboratory testing methods and models often used to describe them. Simple shear testing allows for the in situ conditions to be replicated; however, several limitations of the device make data interpretation difficult. The inability to apply complementary shear stresses and the inability to measure the horizontal normal stresses results in non-uniform stresses across the boundaries, as well as an undefined stress state during shearing. This, in turn, requires assumptions to be made about the failure conditions before any state parameters can be determined. Even when only monotonic testing is conducted, there are still many important questions to be answered about the actual severity of the non-uniform stresses on the boundaries, as well as the internal stresses and the microscopic response of granular soils. Discrete element method (DEM) modeling has the advantage of being able to examine particle-to-particle interactions. Once validated with the measured laboratory data, these models provide a vast quantity of information about the fundamental mechanisms underlying the observed complexity of the response of the soil mass as a whole. The goal of this research is to gain insight into the particle-to-particle interactions driving the overall response of granular samples subjected to multi-directional cyclic simple shear conditions. The main objectives of this proposed project are to (1) characterize the macroscopic response of metal ballotini representing idealized sand under simple shear loading conditions and (2) model the physical element tests using DEM simulations to gain insight into the microscopic response of the granular material. Findings from this study showed that the DEM simulations could be successfully validated by laboratory data and that the overall trends observed agreed reasonably well with the experimental data from this study, as well as previous studies by other researchers. Analyses showed that density not only influences shear strength of a sample, it also affects the angle of shearing resistance, the magnitude of principal stress rotation, the angle of non-co axiality, and the orientation of the principal fabrics for strains below those needed to reach critical state. Vertical effective stress was instead shown to have very little influence on these… Advisors/Committee Members: Biscontin, Giovanna (advisor), Briaud, Jean-Louis (committee member), Hurlebaus, Stefan (committee member), Warden, Robert B. (committee member), O'Sullivan, Catherine (committee member).

Subjects/Keywords: Discrete Element Method; DEM; simple shear; granular material; sand

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bernhardt, M. L. (2013). Examination of Granular Material Behavior in a Laminar-type Direct Simple Shear Device using Laboratory Validated Discrete Element Method Simulations. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/151646

Chicago Manual of Style (16^th Edition):

Bernhardt, Michelle Lee. “Examination of Granular Material Behavior in a Laminar-type Direct Simple Shear Device using Laboratory Validated Discrete Element Method Simulations.” 2013. Doctoral Dissertation, Texas A&M University. Accessed April 13, 2021. http://hdl.handle.net/1969.1/151646.

MLA Handbook (7^th Edition):

Bernhardt, Michelle Lee. “Examination of Granular Material Behavior in a Laminar-type Direct Simple Shear Device using Laboratory Validated Discrete Element Method Simulations.” 2013. Web. 13 Apr 2021.

Vancouver:

Bernhardt ML. Examination of Granular Material Behavior in a Laminar-type Direct Simple Shear Device using Laboratory Validated Discrete Element Method Simulations. [Internet] [Doctoral dissertation]. Texas A&M University; 2013. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1969.1/151646.

Council of Science Editors:

Bernhardt ML. Examination of Granular Material Behavior in a Laminar-type Direct Simple Shear Device using Laboratory Validated Discrete Element Method Simulations. [Doctoral Dissertation]. Texas A&M University; 2013. Available from: http://hdl.handle.net/1969.1/151646

University of Newcastle

10. Tan, Shengming. Dynamic analysis of non-steady flow in granular dense phase pneumatic conveying.

Degree: PhD, 2009, University of Newcastle

URL: http://hdl.handle.net/1959.13/41765

►

Research Doctorate - Doctor of Philosophy (PhD)

Slug flow dense phase pneumatic conveying can be a most reliable, efficient method for handling a remarkably wide… (more)

▼

Research Doctorate - Doctor of Philosophy (PhD)

Slug flow dense phase pneumatic conveying can be a most reliable, efficient method for handling a remarkably wide range of dry bulk solids. Models for pressure drop over slugs in the low-velocity slug-flow pneumatic conveying by many researchers only took the force balance into account with the pressure drop. However, the nature of the slug flow pneumatic conveying is discontinuous and seldom becomes steady during the conveying period which requires further investigation. The fundamental understanding to gas/slug interaction in this thesis is that, by being a dynamic system, the faster a slug moves at a speed, the larger the space is left behind the slug. The gas feeding into the conveying system has to fill the increased space first then permeates through the slug and provides a push force on the slug. With gas permeation rate defined by the permeability factor, the derivative of the upstream pressure based on the air mass conservation law has been developed. For a given conveying system, the pressure in the pneumatic conveying system can be solved for steady conditions or numerically simulated for unsteady conditions. Parametric analysis have been conducted for pressure drop factors and found that slug velocity is the major reason causing the pressure fluctuation in the pneumatic conveying system. To verify the pressure drop model, this model has been applied to single slug cases and compared with experimental results for five different bulk materials, showing good results. Three distinct zones, i.e. Fixed Bed Zone, Initial Slug Zone and Reliable Slug Zone, have been found to exist in the relationship between slip velocity and pressure gradient. Lastly this model has also been applied to a multiple slug system under uniform conditions. In all, the fundamental gas pressure/pressure drop model developed in this thesis approaches slug flow conveying from a different viewpoint from the traditional momentum and material stress models developed by previous researchers, and provides a way of assessing the non-steady flow behaviour in granular dense phase pneumatic conveying. This model not only attains a better understanding of slug flow behaviour but also increases the accuracy of predicting the parameters.

Advisors/Committee Members: University of Newcastle. Faculty of Engineering and Built Environment, School of Engineering.

Subjects/Keywords: pneumatic conveying; slug flow; granular material; dense phase; non-steady flow

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APA (6^th Edition):

Tan, S. (2009). Dynamic analysis of non-steady flow in granular dense phase pneumatic conveying. (Doctoral Dissertation). University of Newcastle. Retrieved from http://hdl.handle.net/1959.13/41765

Chicago Manual of Style (16^th Edition):

Tan, Shengming. “Dynamic analysis of non-steady flow in granular dense phase pneumatic conveying.” 2009. Doctoral Dissertation, University of Newcastle. Accessed April 13, 2021. http://hdl.handle.net/1959.13/41765.

MLA Handbook (7^th Edition):

Tan, Shengming. “Dynamic analysis of non-steady flow in granular dense phase pneumatic conveying.” 2009. Web. 13 Apr 2021.

Vancouver:

Tan S. Dynamic analysis of non-steady flow in granular dense phase pneumatic conveying. [Internet] [Doctoral dissertation]. University of Newcastle; 2009. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1959.13/41765.

Council of Science Editors:

Tan S. Dynamic analysis of non-steady flow in granular dense phase pneumatic conveying. [Doctoral Dissertation]. University of Newcastle; 2009. Available from: http://hdl.handle.net/1959.13/41765

11. Valencia Madrid , Juan Carlos. Estudio experimental de resistencia y fractura de partículas esféricas no saturadas .

Degree: 2013, Universidad de los Andes

URL: http://documentodegrado.uniandes.edu.co/documentos/200521467_fecha_2015_01_14_hora_18_15_33_parte_1.pdf

► En este estudio se diseñó un proceso experimental donde se fabricaron esferas de mortero de diferentes tamaños y resistencias que fueron acondicionadas a diferentes humedades… (more)

Subjects/Keywords: Material granular; succión; emisión acústica.

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APA (6^th Edition):

Valencia Madrid , J. C. (2013). Estudio experimental de resistencia y fractura de partículas esféricas no saturadas . (Thesis). Universidad de los Andes. Retrieved from http://documentodegrado.uniandes.edu.co/documentos/200521467_fecha_2015_01_14_hora_18_15_33_parte_1.pdf

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Valencia Madrid , Juan Carlos. “Estudio experimental de resistencia y fractura de partículas esféricas no saturadas .” 2013. Thesis, Universidad de los Andes. Accessed April 13, 2021. http://documentodegrado.uniandes.edu.co/documentos/200521467_fecha_2015_01_14_hora_18_15_33_parte_1.pdf.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Valencia Madrid , Juan Carlos. “Estudio experimental de resistencia y fractura de partículas esféricas no saturadas .” 2013. Web. 13 Apr 2021.

Vancouver:

Valencia Madrid JC. Estudio experimental de resistencia y fractura de partículas esféricas no saturadas . [Internet] [Thesis]. Universidad de los Andes; 2013. [cited 2021 Apr 13]. Available from: http://documentodegrado.uniandes.edu.co/documentos/200521467_fecha_2015_01_14_hora_18_15_33_parte_1.pdf.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Valencia Madrid JC. Estudio experimental de resistencia y fractura de partículas esféricas no saturadas . [Thesis]. Universidad de los Andes; 2013. Available from: http://documentodegrado.uniandes.edu.co/documentos/200521467_fecha_2015_01_14_hora_18_15_33_parte_1.pdf

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Wollongong

12. Grima, Andrew Phillip. Quantifying and modelling mechanisms of flow in cohesionless and cohesive granular materials.

Degree: PhD, 2011, University of Wollongong

URL: 0913 MECHANICAL ENGINEERING ; https://ro.uow.edu.au/theses/3425

► Discrete element modelling is gradually becoming more popular as a validation tool by industry to simulate bulk flow in bulk material handling and processing… (more)

▼ Discrete element modelling is gradually becoming more popular as a validation tool by industry to simulate bulk flow in bulk material handling and processing equipment. Although discrete element method (DEM) is a popular numerical method in academia to model the complex interactions in particle systems, the demand for the application of DEM to industrial problems is high. The use of DEM simulations to evaluate the flow of bulk materials through belt conveyor transfer points is popular to assist designers to trouble-shoot and quantify the functionality of a design. DEM does not directly design bulk material handling and processing equipment or replace design know-how but DEM simulation is an alternative approach to model particle flow that has traditionally been analysed using analytical methods, empirical design rules and scale model physical prototyping. Calibrated DEM simulations provide additional confidence of the performance of equipment and improve the efficiency and life of equipment due to the significant amounts of quantitative data available to provide insight into the complex physical interactions that occur. Recently there has been a growth of available commercial DEM programs such as EDEM®, which has been utilised in this study, but calibration and validation of DEM simulations still requires further investigation to adequately characterise and model cohesionless and cohesive bulk materials with realism. Insufficient calibration of DEM models can lead to unrealistic predictions making DEM a misleading design validation tool and may lead to poor performing equipment that can be costly to repair. The purpose of this research was to develop techniques to calibrate DEM models based on physical bench scale tests which reproduce the bulk flow behaviours to be modelled on a larger industrial scale. Cohesionless and cohesive bulk materials including polyethylene pellets, coal and bauxite were examined to characterise and develop a set of realistic particle-to-particle and particle-to-boundary interaction parameters for DEM simulations. The accuracy of the characterisation and calibration procedures were examined by modelling the impingement of polyethylene pellets against a flat impact plate using a novel conveyor transfer research facility where experimental quantitative and qualitative data was compared against the DEM simulations and analytical methods. Additional to the latter experimental test program, DEM simulations were conducted on a large scale industrial transfer point to model the flow of wet and sticky bauxite where results from the DEM models were evaluated against the limited quantitative information measured and observations from an existing transfer station. The aim of this thesis was to provide industry with some validated techniques to develop a calibrated DEM model to simulate the flow of bulk materials through complex transfer points and examine the accuracy of the predictions and limitations of DEM. It has been found that some DEM parameters are sensitive,…

Subjects/Keywords: discrete element method; bulk materials handling; numerical calibration; granular material

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Grima, A. P. (2011). Quantifying and modelling mechanisms of flow in cohesionless and cohesive granular materials. (Doctoral Dissertation). University of Wollongong. Retrieved from 0913 MECHANICAL ENGINEERING ; https://ro.uow.edu.au/theses/3425

Chicago Manual of Style (16^th Edition):

Grima, Andrew Phillip. “Quantifying and modelling mechanisms of flow in cohesionless and cohesive granular materials.” 2011. Doctoral Dissertation, University of Wollongong. Accessed April 13, 2021. 0913 MECHANICAL ENGINEERING ; https://ro.uow.edu.au/theses/3425.

MLA Handbook (7^th Edition):

Grima, Andrew Phillip. “Quantifying and modelling mechanisms of flow in cohesionless and cohesive granular materials.” 2011. Web. 13 Apr 2021.

Vancouver:

Grima AP. Quantifying and modelling mechanisms of flow in cohesionless and cohesive granular materials. [Internet] [Doctoral dissertation]. University of Wollongong; 2011. [cited 2021 Apr 13]. Available from: 0913 MECHANICAL ENGINEERING ; https://ro.uow.edu.au/theses/3425.

Council of Science Editors:

Grima AP. Quantifying and modelling mechanisms of flow in cohesionless and cohesive granular materials. [Doctoral Dissertation]. University of Wollongong; 2011. Available from: 0913 MECHANICAL ENGINEERING ; https://ro.uow.edu.au/theses/3425

University of Cambridge

13. Taylor, Nicholas. Hot spots in ammonium nitrate.

Degree: PhD, 2011, University of Cambridge

URL: http://www.dspace.cam.ac.uk/handle/1810/239412https://www.repository.cam.ac.uk/bitstream/1810/239412/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/239412/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/239412/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/239412/8/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/9/thesis.pdf.jpg

► Ammonium nitrate (AN) is commonly used as an explosive and as a fertilizer. In both roles it is provided as prills or pellets, approximately spherical… (more)

▼ Ammonium nitrate (AN) is commonly used as an explosive and as a fertilizer. In both roles it is provided as prills or pellets, approximately spherical and a few millimetres in diameter. The microstructures of several commercially-available AN compositions were investigated using environmental scanning electron microscopy (ESEM) and X-ray microtomography. Those intended for explosive use were found to be more porous than those intended for fertilizer use. The pores in explosive prills were also found to form a connected network. The elemental composition of pellets of mixed AN and dolomite was investigated using energy-dispersive X-ray spectroscopy (EDX); the dolomite additive was found to take the form of grains roughly 50 μm in size. The compaction behaviour of confined cylindrical beds of these prills and pellets was studied at strain rates between 4 × 10−4 s−1 and 200 s−1. Quasi-static experiments were performed using a screw-driven instrumented press, while higher-rate experiments used a drop weight, instrumented with a line laser and load cell. The resistance of a bed to compaction was found to depend on the microstructure of its prills in most cases. Denser prills offered greater resistance to compaction. The exception to this rule was a pellet, rather than prill, formulation. Beds were also found to offer more resistance to compaction at higher strain rates. The Kawakita compaction model was found to agree well with the experimental data. A commercial fertilizer, not containing any AN, was assessed for use as an inert mock for AN prills and pellets. Prills of a suitable size for this purpose were found using EDX to consist of P2O5, with a coating of unknown composition. They were supplied mixed with smaller K2CO3 and urea prills. The mixture was found to have comparable compaction behaviour to AN compositions, indicating that it was useful as a mock for those compositions. In a plate impact experiment on a single layer of P2O5 prills, very little light was observed. This indicated that these prills were sufficiently inert for these purposes. The light produced by shocked granular ammonium nitrate beds and single prill layers was investigated using high-speed framing photography, photodiodes and gated visible-light spectroscopy. Framing photography of prill layers suggested that reaction in prill beds was dominated by effects internal to prills. This was further supported by the similarity between photodiode recordings of prill beds and beds of inert prills containing a single reactive prills. Framing photography of drop weight experiments searching for a mechanism for initiation of reaction by interaction between prills found nothing. Decay of the light output of the beds suggested that in both granular and prill beds this light output was due to small regions heated to thousands of kelvin, which then cooled. Spectroscopic study confirmed this. These regions were found to reach a peak temperature of 6660 ± 20 K, well in excess of the approximately 2000 K predicted by a simple chemical model.…

Subjects/Keywords: Energetic materials; Ammonium nitrate; Detonation; Shock; Granular material; Compaction

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APA (6^th Edition):

Taylor, N. (2011). Hot spots in ammonium nitrate. (Doctoral Dissertation). University of Cambridge. Retrieved from http://www.dspace.cam.ac.uk/handle/1810/239412https://www.repository.cam.ac.uk/bitstream/1810/239412/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/239412/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/239412/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/239412/8/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/9/thesis.pdf.jpg

Chicago Manual of Style (16^th Edition):

Taylor, Nicholas. “Hot spots in ammonium nitrate.” 2011. Doctoral Dissertation, University of Cambridge. Accessed April 13, 2021. http://www.dspace.cam.ac.uk/handle/1810/239412https://www.repository.cam.ac.uk/bitstream/1810/239412/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/239412/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/239412/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/239412/8/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/9/thesis.pdf.jpg.

MLA Handbook (7^th Edition):

Taylor, Nicholas. “Hot spots in ammonium nitrate.” 2011. Web. 13 Apr 2021.

Vancouver:

Taylor N. Hot spots in ammonium nitrate. [Internet] [Doctoral dissertation]. University of Cambridge; 2011. [cited 2021 Apr 13]. Available from: http://www.dspace.cam.ac.uk/handle/1810/239412https://www.repository.cam.ac.uk/bitstream/1810/239412/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/239412/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/239412/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/239412/8/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/9/thesis.pdf.jpg.

Council of Science Editors:

Taylor N. Hot spots in ammonium nitrate. [Doctoral Dissertation]. University of Cambridge; 2011. Available from: http://www.dspace.cam.ac.uk/handle/1810/239412https://www.repository.cam.ac.uk/bitstream/1810/239412/2/license.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/3/license_url ; https://www.repository.cam.ac.uk/bitstream/1810/239412/4/license_text ; https://www.repository.cam.ac.uk/bitstream/1810/239412/5/license_rdf ; https://www.repository.cam.ac.uk/bitstream/1810/239412/8/thesis.pdf.txt ; https://www.repository.cam.ac.uk/bitstream/1810/239412/9/thesis.pdf.jpg

14. Kuwano, Reiko. The stiffness and yielding anisotrophy of sand.

Degree: PhD, 1999, Imperial College London

URL: http://hdl.handle.net/10044/1/8111

Subjects/Keywords: 631.4; Granular material; Failure

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APA (6^th Edition):

Kuwano, R. (1999). The stiffness and yielding anisotrophy of sand. (Doctoral Dissertation). Imperial College London. Retrieved from http://hdl.handle.net/10044/1/8111

Chicago Manual of Style (16^th Edition):

Kuwano, Reiko. “The stiffness and yielding anisotrophy of sand.” 1999. Doctoral Dissertation, Imperial College London. Accessed April 13, 2021. http://hdl.handle.net/10044/1/8111.

MLA Handbook (7^th Edition):

Kuwano, Reiko. “The stiffness and yielding anisotrophy of sand.” 1999. Web. 13 Apr 2021.

Vancouver:

Kuwano R. The stiffness and yielding anisotrophy of sand. [Internet] [Doctoral dissertation]. Imperial College London; 1999. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/10044/1/8111.

Council of Science Editors:

Kuwano R. The stiffness and yielding anisotrophy of sand. [Doctoral Dissertation]. Imperial College London; 1999. Available from: http://hdl.handle.net/10044/1/8111

15. Hedman, Stefan. Smooth and non-smooth approaches to simulation of granular matter.

Degree: Physics, 2011, Umeå University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-50584

► Granular matter is defined as a collection of particle grains, such as sand.This type of matter have different characteristics (solid, liquid and gas) depending… (more)

Subjects/Keywords: granular material; contact dynamics; DEM; discrete element method

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APA (6^th Edition):

Hedman, S. (2011). Smooth and non-smooth approaches to simulation of granular matter. (Thesis). Umeå University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-50584

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Hedman, Stefan. “Smooth and non-smooth approaches to simulation of granular matter.” 2011. Thesis, Umeå University. Accessed April 13, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-50584.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Hedman, Stefan. “Smooth and non-smooth approaches to simulation of granular matter.” 2011. Web. 13 Apr 2021.

Vancouver:

Hedman S. Smooth and non-smooth approaches to simulation of granular matter. [Internet] [Thesis]. Umeå University; 2011. [cited 2021 Apr 13]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-50584.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Hedman S. Smooth and non-smooth approaches to simulation of granular matter. [Thesis]. Umeå University; 2011. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-50584

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology

16. Lukkezen, T.L. (author). Implementation and inspection of a high-cycle accumulation model.

Degree: 2016, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:51cbcc49-b579-459d-beec-fa23e1dcc830

►

The prediction of permanent deformation accretion in granular materials as a result of long-term cyclic loading is a complex challenge that receives great attention in… (more)

▼

The prediction of permanent deformation accretion in granular materials as a result of long-term cyclic loading is a complex challenge that receives great attention in engineering fields, including infrastructural design and design of offshore wind turbines. Many models have been proposed in the past which aim to predict this cyclic deformation accumulation for specific or general purpose. One of the most advanced models available is the "High-Cycle Accumulation (HCA) model" byNiemunis et al (2005) [1]. Although very promising, this model is as of yet rarely used in Dutch geotechnical engineering practice. One of the possible reasons for this is the lack of understanding and availability of the model. This thesis has the aim to overcome these problems by gathering relevant information on the HCA model, implementing it in Plaxis 2D finite element software and inspecting the capabilities of the resulting FE routine. After gathering the information on the model from literature, it was concluded that the model has great potential and is themost extensively validated model available. However, there are also some boundary conditions for which the model fails to predict the deformations correctly. The model also requires a vast number of advanced laboratory tests to be carried out in order to compute the model parameters. The implementation of the constitutive equations in Plaxis 2D was performed successfully and was verified for a single-element type case. When applying the FE routine to a boundary value problem, numerical issues arising from the finite element calculation kernel conflict with the sensitivity of the HCA model to the state parameters, resulting in a severe over-estimation of accumulated settlements. A sensitivity analysis was carried out, which shows that the model is highly sensitive to the parameters of the hypoplastic model (which is used in the initial calculation phase of the FE routine). It is concluded that for the HCA routine to be used in Plaxis, the numerical issues should be investigated and possibly a numerical interface should be designed. The high sensitivity to the model parameters, combined with the vast amount of required effort (and cost) to compute these parameters for a sand sample make the model less favourable for practical design applications.

Civil Engineering and Geosciences

Geoscience and Engineering

Geo-engineering

Advisors/Committee Members: Hicks, M.A. (mentor).

Subjects/Keywords: cyclic loading; strain accumulation; granular material; sand; shallow foundation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lukkezen, T. L. (. (2016). Implementation and inspection of a high-cycle accumulation model. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:51cbcc49-b579-459d-beec-fa23e1dcc830

Chicago Manual of Style (16^th Edition):

Lukkezen, T L (author). “Implementation and inspection of a high-cycle accumulation model.” 2016. Masters Thesis, Delft University of Technology. Accessed April 13, 2021. http://resolver.tudelft.nl/uuid:51cbcc49-b579-459d-beec-fa23e1dcc830.

MLA Handbook (7^th Edition):

Lukkezen, T L (author). “Implementation and inspection of a high-cycle accumulation model.” 2016. Web. 13 Apr 2021.

Vancouver:

Lukkezen TL(. Implementation and inspection of a high-cycle accumulation model. [Internet] [Masters thesis]. Delft University of Technology; 2016. [cited 2021 Apr 13]. Available from: http://resolver.tudelft.nl/uuid:51cbcc49-b579-459d-beec-fa23e1dcc830.

Council of Science Editors:

Lukkezen TL(. Implementation and inspection of a high-cycle accumulation model. [Masters Thesis]. Delft University of Technology; 2016. Available from: http://resolver.tudelft.nl/uuid:51cbcc49-b579-459d-beec-fa23e1dcc830

University of Arkansas

17. Watters, Matthew P. Feasibility of Additive Manufactured Materials for Use in Geotechnical Laboratory Testing Applications.

Degree: MSCE, 2017, University of Arkansas

URL: https://scholarworks.uark.edu/etd/1973

► The factors affecting the positive volumetric strain, or dilatancy, typically observed in response to shearing of a dense granular material have long been investigated;… (more)

Subjects/Keywords: Analogue soil; Granular material; Triaxial; Civil Engineering; Geotechnical Engineering

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APA (6^th Edition):

Watters, M. P. (2017). Feasibility of Additive Manufactured Materials for Use in Geotechnical Laboratory Testing Applications. (Masters Thesis). University of Arkansas. Retrieved from https://scholarworks.uark.edu/etd/1973

Chicago Manual of Style (16^th Edition):

Watters, Matthew P. “Feasibility of Additive Manufactured Materials for Use in Geotechnical Laboratory Testing Applications.” 2017. Masters Thesis, University of Arkansas. Accessed April 13, 2021. https://scholarworks.uark.edu/etd/1973.

MLA Handbook (7^th Edition):

Watters, Matthew P. “Feasibility of Additive Manufactured Materials for Use in Geotechnical Laboratory Testing Applications.” 2017. Web. 13 Apr 2021.

Vancouver:

Watters MP. Feasibility of Additive Manufactured Materials for Use in Geotechnical Laboratory Testing Applications. [Internet] [Masters thesis]. University of Arkansas; 2017. [cited 2021 Apr 13]. Available from: https://scholarworks.uark.edu/etd/1973.

Council of Science Editors:

Watters MP. Feasibility of Additive Manufactured Materials for Use in Geotechnical Laboratory Testing Applications. [Masters Thesis]. University of Arkansas; 2017. Available from: https://scholarworks.uark.edu/etd/1973

University of Cambridge

18. Taylor, Nicholas. Hot spots in ammonium nitrate.

Degree: PhD, 2011, University of Cambridge

URL: https://doi.org/10.17863/CAM.16578 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541934

► Ammonium nitrate (AN) is commonly used as an explosive and as a fertilizer. In both roles it is provided as prills or pellets, approximately spherical… (more)

▼ Ammonium nitrate (AN) is commonly used as an explosive and as a fertilizer. In both roles it is provided as prills or pellets, approximately spherical and a few millimetres in diameter. The microstructures of several commercially-available AN compositions were investigated usingenvironmental scanning electron microscopy (ESEM) and X-ray microtomography. Those intended for explosive use were found to bemore porous than those intended for fertilizer use. The pores in explosiveprills were also found to form a connected network. The elemental composition of pellets of mixed AN and dolomite was investigated using energy-dispersive X-ray spectroscopy (EDX); the dolomite additivewas found to take the form of grains roughly 50 μm in size. The compaction behaviour of confined cylindrical beds of these prillsand pellets was studied at strain rates between 4 x 10-4 s-1 and 200 s-1. Quasi-static experiments were performed using a screw-driven instrumented press, while higher-rate experiments used a drop weight,instrumented with a line laser and load cell. The resistance of a bed to compaction was found to depend on the microstructure of its prills in most cases. Denser prills offered greater resistance to compaction. The exception to this rule was a pellet, rather than prill, formulation. Beds were also found to offer more resistance to compaction at higher strain rates. The Kawakita compaction model was found to agree well with the experimental data. A commercial fertilizer, not containing any AN, was assessed for use as an inert mock for AN prills and pellets. Prills of a suitable size for this purpose were found using EDX to consist of P2O5, with a coatingof unknown composition. They were supplied mixed with smaller K2CO3 and urea prills. The mixture was found to have comparablecompaction behaviour to AN compositions, indicating that it was useful as a mock for those compositions. In a plate impact experiment on a single layer of P2O5 prills, very little light was observed. Thisindicated that these prills were sufficiently inert for these purposes. The light produced by shocked granular ammonium nitrate beds and single prill layers was investigated using high-speed framing photography, photodiodes and gated visible-light spectroscopy. Framing photography of prill layers suggested that reaction in prill beds was dominatedby effects internal to prills. This was further supported by the similarity between photodiode recordings of prill beds and beds of inert prills containing a single reactive prills. Framing photography of drop weight experiments searching for a mechanism for initiation of reaction by interaction between prills found nothing. Decay of the light output of the beds suggested that in both granularand prill beds this light output was due to small regions heated to thousands of kelvin, which then cooled. Spectroscopic study confirmed this. These regions were found to reach a peak temperature of 6660 ± 20 K, well in excess of the approximately 2000 K predicted by a simple chemical model. Investigation of spectral…

Subjects/Keywords: 620.112; s; Ammonium nitrate; Detonation; Shock; Granular material; Compaction

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Taylor, N. (2011). Hot spots in ammonium nitrate. (Doctoral Dissertation). University of Cambridge. Retrieved from https://doi.org/10.17863/CAM.16578 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541934

Chicago Manual of Style (16^th Edition):

Taylor, Nicholas. “Hot spots in ammonium nitrate.” 2011. Doctoral Dissertation, University of Cambridge. Accessed April 13, 2021. https://doi.org/10.17863/CAM.16578 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541934.

MLA Handbook (7^th Edition):

Taylor, Nicholas. “Hot spots in ammonium nitrate.” 2011. Web. 13 Apr 2021.

Vancouver:

Taylor N. Hot spots in ammonium nitrate. [Internet] [Doctoral dissertation]. University of Cambridge; 2011. [cited 2021 Apr 13]. Available from: https://doi.org/10.17863/CAM.16578 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541934.

Council of Science Editors:

Taylor N. Hot spots in ammonium nitrate. [Doctoral Dissertation]. University of Cambridge; 2011. Available from: https://doi.org/10.17863/CAM.16578 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.541934

UCLA

19. Gast, Theodore Finn. Numerical Simulation of Elastic, Viscoelastic, and Granular Materials.

Degree: Mathematics, 2016, UCLA

URL: http://www.escholarship.org/uc/item/0vr7h3j7

► Practical time steps in today's state-of-the-art simulators typically rely on Newton's method to solve large systems of nonlinear equations. In practice, this works well for… (more)

▼ Practical time steps in today's state-of-the-art simulators typically rely on Newton's method to solve large systems of nonlinear equations. In practice, this works well for small time steps but is unreliable at large time steps at or near the frame rate, particularly for difficult or stiff simulations. Recasting backward Euler as a minimization problem allows Newton's method to be stabilized by standard optimization techniques. The resulting solver is capable of solving even the toughest simulations at the 24Hz frame rate and beyond. Simple collisions can be incorporated directly into the solver through constrained minimization without sacrificing efficiency. Several collision formulations are presented including for self collisions and collisions against scripted bodies, which are designed for the unique demands of this solver. Finally the Material Point Method (MPM) can be formulated to use the solver, and we present formulations for its use for simulating various materials.For simulating viscoelastic fluids, foams and sponges, we design our discretization from the upper convected derivative terms in the evolution of the left Cauchy-Green elastic strain tensor. We combine this with an Oldroyd-B model for plastic flow in a complex viscoelastic fluid. While the Oldroyd-B model is traditionally used for viscoelastic fluids, we show that its interpretation as a plastic flow naturally allows us to simulate a wide range of complex material behaviors. In order to do this, we provide a modification to the traditional Oldroyd- B model that guarantees volume preserving plastic flows. Our plasticity model is remarkablysimple (foregoing the need for the singular value decomposition (SVD) of stresses or strains). We show that implicit time stepping can be achieved with an optimization based approach and that this allows for high resolution simulations at practical simulation times.We demonstrate that the Drucker-Prager plastic flow model combined with a Hencky-strain-based hyperelasticity accurately recreates a wide range of visual sand phenomena with moderate computational expense. We use the Material Point Method (MPM) to discretize the governing equations for its natural treatment of contact, topological change and history dependent constitutive relations. The Drucker-Prager model naturally represents the frictional relation between shear and normal stresses through a yield stress criterion. We develop a stress projection algorithm used for enforcing this condition with a non-associative flow rule that works naturally with both implicit (non-optimization based) and explicit time integration. We demonstrate the efficacy of our approach on examples undergoing large deformation, collisions and topological changes necessary for producing modern visual effects.

Subjects/Keywords: Applied mathematics; Computer science; Granular; Material Point Method; Nonlinear Optimization; Numerical Simulation; Viscoelastic

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APA (6^th Edition):

Gast, T. F. (2016). Numerical Simulation of Elastic, Viscoelastic, and Granular Materials. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/0vr7h3j7

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gast, Theodore Finn. “Numerical Simulation of Elastic, Viscoelastic, and Granular Materials.” 2016. Thesis, UCLA. Accessed April 13, 2021. http://www.escholarship.org/uc/item/0vr7h3j7.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gast, Theodore Finn. “Numerical Simulation of Elastic, Viscoelastic, and Granular Materials.” 2016. Web. 13 Apr 2021.

Vancouver:

Gast TF. Numerical Simulation of Elastic, Viscoelastic, and Granular Materials. [Internet] [Thesis]. UCLA; 2016. [cited 2021 Apr 13]. Available from: http://www.escholarship.org/uc/item/0vr7h3j7.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gast TF. Numerical Simulation of Elastic, Viscoelastic, and Granular Materials. [Thesis]. UCLA; 2016. Available from: http://www.escholarship.org/uc/item/0vr7h3j7

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

UCLA

20. Klar, Gergely. Simulation of Granular Media with the Material Point Method.

Degree: Computer Science, 2016, UCLA

URL: http://www.escholarship.org/uc/item/5th3x8fb

► We propose an extension to the Material Point Method for the simulation of granular media. We model the dynamics with an elastoplastic, continuum assumption. The… (more)

Subjects/Keywords: Computer science; Applied mathematics; Drucker Prager; granular; material point method; MPM; sand; simulation

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APA (6^th Edition):

Klar, G. (2016). Simulation of Granular Media with the Material Point Method. (Thesis). UCLA. Retrieved from http://www.escholarship.org/uc/item/5th3x8fb

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Klar, Gergely. “Simulation of Granular Media with the Material Point Method.” 2016. Thesis, UCLA. Accessed April 13, 2021. http://www.escholarship.org/uc/item/5th3x8fb.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Klar, Gergely. “Simulation of Granular Media with the Material Point Method.” 2016. Web. 13 Apr 2021.

Vancouver:

Klar G. Simulation of Granular Media with the Material Point Method. [Internet] [Thesis]. UCLA; 2016. [cited 2021 Apr 13]. Available from: http://www.escholarship.org/uc/item/5th3x8fb.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Klar G. Simulation of Granular Media with the Material Point Method. [Thesis]. UCLA; 2016. Available from: http://www.escholarship.org/uc/item/5th3x8fb

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Georgia Tech

21. Wang, Pei. Micro-mechanical analysis of quasi-static particulate fragmentation applied to geomaterials.

Degree: PhD, Civil and Environmental Engineering, 2019, Georgia Tech

URL: http://hdl.handle.net/1853/61220

► Despite the progress made on modeling granular mechanics at the macro-scale, discriminating the mechanisms that control particle breakage within a particulate assembly is still an… (more)

▼ Despite the progress made on modeling granular mechanics at the macro-scale, discriminating the mechanisms that control particle breakage within a particulate assembly is still an open issue. In this thesis, we analyze particle fragmentation and the associated energy distribution from a micro-mechanical standpoint. First, we explain the state of the art in terms of micro-macro modeling of breakage in granular assemblies, and we present in detail the pros and cons of the techniques employed in the Discrete Element Method (DEM) to simulate particle crushing. Second, we conduct a numerical study at the particle scale to understand in which conditions shielding effects overcome size effects. We also investigate the influence of microscopic flaws on particle crushing. Our simulations highlight the predominant influence of porosity over flaw size and show that particle strength depends linearly on the particle coordination number and quadratically on particle porosity. Third, we analyze micro-CT scans obtained sequentially during an oedometer test of zeolite to model crushing at the scale of a granular assembly. We implement a new breakage model in DEM, which combines particle replacement, for primary splitting breakage, and cluster bond breakage, for modeling for fragment breakage. The PSD obtained with the new DEM model exhibited an impressive matching with experimental results. Fourth, we analyze the evolution of the energy of a granular assembly subject to particulate breakage during quasi-static confined comminution. Energy potentials are related to internal variables that have a clear relationship to microstructure evolution, e.g. deviation to initial and ultimate PSDs, particle specific surface, porosity. DEM simulations show that: At least 60% of the work input is dissipated by particle redistribution; The breakage energy accounts for less than 5% of the total input energy; The energy dissipated by redistribution is between 14 to 30 times larger than the breakage energy. Lastly, we propose a DEM displacement-softening contact model to simulate fracture propagation in concrete. We calibrate the model with results of uniaxial compression tests and Brazilian tests of both mortar and concrete. DEM simulations confirm that concrete does not fail in pure tensile mode during Brazilian tests. Sensitivity analyses also show that concrete strength depends linearly on both the adhesive area fraction of the ITZ and the aggregate tensile strength. The ITZ has a greater effect on concrete strength than aggregate strength. Future studies will focus on the modeling of various simultaneous breakage mechanisms (e.g. splitting, multi-fragmentation, chipping, erosion) and on their relation to the macroscopic response of the granular assembly, as well as the modeling of cyclic effects, the prediction of bond corrosion in the presence of water, and the design of bond reparation. Advisors/Committee Members: Arson, Chloé (advisor), Neu, Richard W. (advisor), Frost, David (advisor), Viggiani, Cino (advisor), Dai, Sheng (advisor).

Subjects/Keywords: Granular material; Breakage; Discrete element modeling; Contact model; Energy distribution; Concrete strength; Interfacial transition zone

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APA (6^th Edition):

Wang, P. (2019). Micro-mechanical analysis of quasi-static particulate fragmentation applied to geomaterials. (Doctoral Dissertation). Georgia Tech. Retrieved from http://hdl.handle.net/1853/61220

Chicago Manual of Style (16^th Edition):

Wang, Pei. “Micro-mechanical analysis of quasi-static particulate fragmentation applied to geomaterials.” 2019. Doctoral Dissertation, Georgia Tech. Accessed April 13, 2021. http://hdl.handle.net/1853/61220.

MLA Handbook (7^th Edition):

Wang, Pei. “Micro-mechanical analysis of quasi-static particulate fragmentation applied to geomaterials.” 2019. Web. 13 Apr 2021.

Vancouver:

Wang P. Micro-mechanical analysis of quasi-static particulate fragmentation applied to geomaterials. [Internet] [Doctoral dissertation]. Georgia Tech; 2019. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1853/61220.

Council of Science Editors:

Wang P. Micro-mechanical analysis of quasi-static particulate fragmentation applied to geomaterials. [Doctoral Dissertation]. Georgia Tech; 2019. Available from: http://hdl.handle.net/1853/61220

Texas A&M University

22. Noble, Patrick. Uncertainty Quantification of the Homogeneity of Granular Materials through Discrete Element Modeling and X-Ray Computed Tomography.

Degree: MS, Civil Engineering, 2012, Texas A&M University

URL: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11828

► Previous research has shown that the sample preparation method used to reconstitute specimens for granular materials can have a significant impact on its mechanistic behavior.… (more)

Subjects/Keywords: Discrete Element Modeling; DEM; X-Ray Computed Tomography; Homogeneity; Homogeneous; Granular Material

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APA (6^th Edition):

Noble, P. (2012). Uncertainty Quantification of the Homogeneity of Granular Materials through Discrete Element Modeling and X-Ray Computed Tomography. (Masters Thesis). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11828

Chicago Manual of Style (16^th Edition):

Noble, Patrick. “Uncertainty Quantification of the Homogeneity of Granular Materials through Discrete Element Modeling and X-Ray Computed Tomography.” 2012. Masters Thesis, Texas A&M University. Accessed April 13, 2021. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11828.

MLA Handbook (7^th Edition):

Noble, Patrick. “Uncertainty Quantification of the Homogeneity of Granular Materials through Discrete Element Modeling and X-Ray Computed Tomography.” 2012. Web. 13 Apr 2021.

Vancouver:

Noble P. Uncertainty Quantification of the Homogeneity of Granular Materials through Discrete Element Modeling and X-Ray Computed Tomography. [Internet] [Masters thesis]. Texas A&M University; 2012. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11828.

Council of Science Editors:

Noble P. Uncertainty Quantification of the Homogeneity of Granular Materials through Discrete Element Modeling and X-Ray Computed Tomography. [Masters Thesis]. Texas A&M University; 2012. Available from: http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11828

McMaster University

23. Karchewski, Brandon. Multi-scale modelling of geomechanical behaviour using the Voronoi cell finite element method (VCFEM) and finite-discrete element method (VCFEM-DEM).

Degree: PhD, 2015, McMaster University

URL: http://hdl.handle.net/11375/18093

►

The present work applies the hybrid Voronoi cell finite element method (VCFEM) within geomechanics. Coupled seepage and deformation analysis using the VCFEM incorporating body forces… (more)

▼

The present work applies the hybrid Voronoi cell finite element method (VCFEM) within geomechanics. Coupled seepage and deformation analysis using the VCFEM incorporating body forces allows accurate analysis of earth dams. The development of a novel approach for simulating granular material behaviour using the combined finite-discrete element method (VCFEM-DEM) provides new insights into strain localization in granular materials. Chapter 1 provides background including summary literature reviews for all concepts in the title including seepage analysis, micromechanical and continuum mechanics theory, Voronoi diagrams, finite elements (FEM), discrete elements (DEM) and combined FEM-DEM. Chapter 1 concludes by detailing the contributions of the present work. Chapter 2 presents the VCFEM for seepage analysis. The numerical examples include an investigation of mesh sensitivity and a comparison of conforming shape functions. Polygonal elements with more than four nodes show a decrease in mesh sensitivity in free surface problems, compared with four-node quadrilateral elements. The choice of conforming shape function within the VCFEM analysis did not affect the results. Chapter 3 formulates and applies the VCFEM-DEM, showing that strain localization effects in granular materials are important at all scales. The VCFEM-DEM captures shear banding in biaxial compression tests, demonstrating that global shear strains and inhomogeneities in the shear stress field present after consolidation are early precursors to the failure mode. At the field scale, strain localization can lead to significant non-uniformity in subsurface stress distribution owing to self-weight. Chapter 4 presents the coupled VCFEM for seepage and deformation. A practical example of the design of an earth dam demonstrates the application of general body forces within a hybrid formulation, notably lacking in the literature. Chapter 5 concludes by summarizing the key observations of the present work, and providing direction for future research. The Appendix provides additional details related to numerical integration within the VCFEM.

Thesis

Doctor of Philosophy (PhD)

The focus of the present work is the simulation of geomechanical behaviour at multiple scales. This ranges from simulating the interaction of grains of sand in a laboratory compression test to the seepage of water through and deformation of a large dam constructed of granular material. The simulations use a numerical tool called the Voronoi cell finite element method (VCFEM), which the present work extends to allow accurate analysis of the flow of fluid through a porous medium, deformation of a granular material under load and coupled analysis of these phenomena. The development and testing of this numerical tool for use in geomechanical analysis is itself a contribution. The present work also contains new insights into how localized stresses and strains in a granular material that are present well before the peak strength can have an important influence on the mode of failure.

Advisors/Committee Members: Stolle, Dieter, Guo, Peijun, Civil Engineering.

Subjects/Keywords: geomechanics; granular material; finite element; discrete element; multi-scale modelling; coupled modelling; Voronoi cell

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APA (6^th Edition):

Karchewski, B. (2015). Multi-scale modelling of geomechanical behaviour using the Voronoi cell finite element method (VCFEM) and finite-discrete element method (VCFEM-DEM). (Doctoral Dissertation). McMaster University. Retrieved from http://hdl.handle.net/11375/18093

Chicago Manual of Style (16^th Edition):

Karchewski, Brandon. “Multi-scale modelling of geomechanical behaviour using the Voronoi cell finite element method (VCFEM) and finite-discrete element method (VCFEM-DEM).” 2015. Doctoral Dissertation, McMaster University. Accessed April 13, 2021. http://hdl.handle.net/11375/18093.

MLA Handbook (7^th Edition):

Karchewski, Brandon. “Multi-scale modelling of geomechanical behaviour using the Voronoi cell finite element method (VCFEM) and finite-discrete element method (VCFEM-DEM).” 2015. Web. 13 Apr 2021.

Vancouver:

Karchewski B. Multi-scale modelling of geomechanical behaviour using the Voronoi cell finite element method (VCFEM) and finite-discrete element method (VCFEM-DEM). [Internet] [Doctoral dissertation]. McMaster University; 2015. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/11375/18093.

Council of Science Editors:

Karchewski B. Multi-scale modelling of geomechanical behaviour using the Voronoi cell finite element method (VCFEM) and finite-discrete element method (VCFEM-DEM). [Doctoral Dissertation]. McMaster University; 2015. Available from: http://hdl.handle.net/11375/18093

Université Montpellier II

24. Nguyen, Duc Hanh. Microstructure et comportement mécanique des milieux granulaires polydispersés fragmentables : Microstructure and mechanical behavior of polydisperse and crushable granular media.

Degree: Docteur es, Mécanique et génie civil, 2014, Université Montpellier II

URL: http://www.theses.fr/2014MON20116

►

L'objectif des travaux présentés dans ce mémoire est de caractériser la texture et la rhéologie des milieux granulaires en fonction de la polydispersité de forme… (more)

▼

L'objectif des travaux présentés dans ce mémoire est de caractériser la texture et la rhéologie des milieux granulaires en fonction de la polydispersité de forme et de taille des particules mais aussi en fonction de la cohésion interne des particules lorsqu'elles sont fragmentables, en vue d'une meilleure compréhension du procédé de fabrication des compacts. Pour ces études, nous avons utilisé la méthode de Dynamique des Contacts avec un modèle de rupture des particules. Nos analyses montrent que la polydispersité de forme peut jouer un rôle important lorsque la polydispersité de taille est faible. Par exemple, la résistance au cisaillement est presque indépendante de la polydispersité de taille mais elle diminue lorsque les formes deviennent plus irrégulières. La fragmentation des particules est fortement hétérogène en raison de la redistribution des contraintes au sein du matériau. Celui-ci garde la mémoire de la distribution granulométrique initiale, mais une classe intermédiaire de tailles se développe avec une distribution en loi de puissance des tailles et un rapport d'aspect moyen proche du nombre d'argent. Au cours du cisaillement, les déformations se localisent dans des bandes avec une compacité supérieure au reste du matériau en raison de la fragmentation des particules. La fragmentation tend également à annuler la dilatance et le pic de contrainte.

The general objective of the work presented in this dissertation is to investigate the microstructure and rheology of granular materials as a function of size and shape polydispersity of the particles, and to analyze the role of particle fragmentation as a function of the internal cohesion of particles in view of a better understanding of the manufacture process of powder compacts. For this work, we used numerical simulations by means of the Contact Dynamics method with a model of particle fracture. Our results suggest that shape polydispersity may play an important role when size polydispersity is low. For example, the shear strength is nearly independent of size distribution but declines when the particles becomes increasingly more irregular in shape. The process of particle fragmentation is found to be highly inhomogenious as a result of stress redistribution. The memory of the initial size distribution is mainly conserved in the class of larger particles while a class of intermediate sizes develops with a power-law size distribution and a mean aspect ratio close to the silver number independently of the initial size distribution. During shear, the strain is localized in shear bands of large solid fraction as a consequence of particle fragmentation and enhanced size polydispersity. Particle fragmentation tends to reduce dilatancy and the peak shear strength.

Advisors/Committee Members: Radjaï, Farhang (thesis director).

Subjects/Keywords: Milieux granulaires; Polydispersité; Microstructure; Fragmentation; Simulation; Rhéologie; Granular material; Polydispersity; Microstructure; Fragmentation; Simulation; Rheology

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APA (6^th Edition):

Nguyen, D. H. (2014). Microstructure et comportement mécanique des milieux granulaires polydispersés fragmentables : Microstructure and mechanical behavior of polydisperse and crushable granular media. (Doctoral Dissertation). Université Montpellier II. Retrieved from http://www.theses.fr/2014MON20116

Chicago Manual of Style (16^th Edition):

Nguyen, Duc Hanh. “Microstructure et comportement mécanique des milieux granulaires polydispersés fragmentables : Microstructure and mechanical behavior of polydisperse and crushable granular media.” 2014. Doctoral Dissertation, Université Montpellier II. Accessed April 13, 2021. http://www.theses.fr/2014MON20116.

MLA Handbook (7^th Edition):

Nguyen, Duc Hanh. “Microstructure et comportement mécanique des milieux granulaires polydispersés fragmentables : Microstructure and mechanical behavior of polydisperse and crushable granular media.” 2014. Web. 13 Apr 2021.

Vancouver:

Nguyen DH. Microstructure et comportement mécanique des milieux granulaires polydispersés fragmentables : Microstructure and mechanical behavior of polydisperse and crushable granular media. [Internet] [Doctoral dissertation]. Université Montpellier II; 2014. [cited 2021 Apr 13]. Available from: http://www.theses.fr/2014MON20116.

Council of Science Editors:

Nguyen DH. Microstructure et comportement mécanique des milieux granulaires polydispersés fragmentables : Microstructure and mechanical behavior of polydisperse and crushable granular media. [Doctoral Dissertation]. Université Montpellier II; 2014. Available from: http://www.theses.fr/2014MON20116

New Jersey Institute of Technology

25. Kovalcinova, Lenka. Numerical simulations of dense granular systems with and without cohesive effects.

Degree: PhD, Mathematical Sciences, 2016, New Jersey Institute of Technology

URL: https://digitalcommons.njit.edu/dissertations/92

► Granular materials are collections of objects ranging from sand grains that form sand piles or even sand castles to collections of large objects such… (more)

▼ Granular materials are collections of objects ranging from sand grains that form sand piles or even sand castles to collections of large objects such as a group of meteors in outer space. The considered range of sizes of granular particles is such that the effect of thermal fluctuations is not relevant. However, the interaction between the particles may be very complex, involving inelasticity and friction, in addition to repulsive and possibly attractive interaction forces. These interactions that may be history dependent, make the systems that consist of a large number of particles complex to analyze and difficult to understand using analytical methods. For this reason, most of the work in the field of granular mater, including the main part of this Thesis, is carried out using discrete element/molecular dynamics type simulations. At the beginning of this work, the energy propagation is considered in a stochastic granular chain in one spatial dimension (1D). The main finding here is that the properties of the stochastic noise influences strongly the process of energy propagation. As it is shown, the issue of the importance of order and randomness remains significant as other aspects of dense granular systems are considered. Next, the various aspects of 2D and 3D granular systems are discussed, with the focus on a dense regime, where the particles are in almost continuous contact. One important property of the considered systems is the presence of force networks, that describe how interactions between the particles are organized spatially, and how they evolve in time. These mesoscale structures are known to be related on one hand to the microscopic properties relevant on the particle scale, and on the other hand to the global properties of considered systems as a whole. Consideration of dense granular systems using the tools of percolation theory illustrates the complex process by which these systems go through percolation and jamming transitions when exposed to compression. One significant finding is that these two transitions may coincide or not, depending on the properties of the granular particles. Furthermore, there is an important influence of the force threshold considered, tracing back to the properties of underlying force networks. These networks are analyzed by considering their scaling properties with respect to the system size. Contrary to the published results, it is found that the properties of these networks are not universal: in particular, the force networks that form in the systems comprising frictionless particles are found to belong to a different universality class. Another approach to analysis of force networks involves consideration of topological measures. In this direction, a novel study involving direct comparison of computational results is carried out analyzing experimental data using the tools of persistence homology, and in particular Betti numbers, that allow to quantify the properties of the force networks, and make comparisons directly between… Advisors/Committee Members: Lou Kondic, Konstantin Michael Mischaikow, Guillaume Bal.

Subjects/Keywords: Granular material; Percolation; Force networks; Stocahstic wave equation; Sheared systems; Numerical simulations; Mathematics

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APA (6^th Edition):

Kovalcinova, L. (2016). Numerical simulations of dense granular systems with and without cohesive effects. (Doctoral Dissertation). New Jersey Institute of Technology. Retrieved from https://digitalcommons.njit.edu/dissertations/92

Chicago Manual of Style (16^th Edition):

Kovalcinova, Lenka. “Numerical simulations of dense granular systems with and without cohesive effects.” 2016. Doctoral Dissertation, New Jersey Institute of Technology. Accessed April 13, 2021. https://digitalcommons.njit.edu/dissertations/92.

MLA Handbook (7^th Edition):

Kovalcinova, Lenka. “Numerical simulations of dense granular systems with and without cohesive effects.” 2016. Web. 13 Apr 2021.

Vancouver:

Kovalcinova L. Numerical simulations of dense granular systems with and without cohesive effects. [Internet] [Doctoral dissertation]. New Jersey Institute of Technology; 2016. [cited 2021 Apr 13]. Available from: https://digitalcommons.njit.edu/dissertations/92.

Council of Science Editors:

Kovalcinova L. Numerical simulations of dense granular systems with and without cohesive effects. [Doctoral Dissertation]. New Jersey Institute of Technology; 2016. Available from: https://digitalcommons.njit.edu/dissertations/92

New Jersey Institute of Technology

26. Zuo, Luo. Dynamics of 1d granular column.

Degree: PhD, Mechanical and Industrial Engineering, 2014, New Jersey Institute of Technology

URL: https://digitalcommons.njit.edu/dissertations/172

► This dissertation is focused on a discrete element study of the dynamics of a one- dimensional column of inelastic spheres that it subjected to… (more)

Subjects/Keywords: Granular material; 1d column; Particle mechanics; Discrete element; Dynamical system; Tap energy; Mechanical Engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zuo, L. (2014). Dynamics of 1d granular column. (Doctoral Dissertation). New Jersey Institute of Technology. Retrieved from https://digitalcommons.njit.edu/dissertations/172

Chicago Manual of Style (16^th Edition):

Zuo, Luo. “Dynamics of 1d granular column.” 2014. Doctoral Dissertation, New Jersey Institute of Technology. Accessed April 13, 2021. https://digitalcommons.njit.edu/dissertations/172.

MLA Handbook (7^th Edition):

Zuo, Luo. “Dynamics of 1d granular column.” 2014. Web. 13 Apr 2021.

Vancouver:

Zuo L. Dynamics of 1d granular column. [Internet] [Doctoral dissertation]. New Jersey Institute of Technology; 2014. [cited 2021 Apr 13]. Available from: https://digitalcommons.njit.edu/dissertations/172.

Council of Science Editors:

Zuo L. Dynamics of 1d granular column. [Doctoral Dissertation]. New Jersey Institute of Technology; 2014. Available from: https://digitalcommons.njit.edu/dissertations/172

27. Lindmark, Daniel. Simulation based exploration of a loading strategy for a LHD-vehicle.

Degree: Physics, 2016, Umeå University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-126419

► Optimizing the loading process of a front loader vehicle is a challenging task. The design space is large and depends on the design of… (more)

Subjects/Keywords: DEM NDEM surrogate models loading strategy granular material Pareto; Physical Sciences; Fysik

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APA (6^th Edition):

Lindmark, D. (2016). Simulation based exploration of a loading strategy for a LHD-vehicle. (Thesis). Umeå University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-126419

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Lindmark, Daniel. “Simulation based exploration of a loading strategy for a LHD-vehicle.” 2016. Thesis, Umeå University. Accessed April 13, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-126419.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Lindmark, Daniel. “Simulation based exploration of a loading strategy for a LHD-vehicle.” 2016. Web. 13 Apr 2021.

Vancouver:

Lindmark D. Simulation based exploration of a loading strategy for a LHD-vehicle. [Internet] [Thesis]. Umeå University; 2016. [cited 2021 Apr 13]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-126419.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Lindmark D. Simulation based exploration of a loading strategy for a LHD-vehicle. [Thesis]. Umeå University; 2016. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-126419

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Universitat Politècnica de València

28. Esquerdo Lloret, Tomás Vicente. DESARROLLO DE MODELOS DE COMPORTAMIENTO ACÚSTICO Y CARACTERIZACIÓN EXPERIMENTAL DE MATERIALES ELABORADOS CON ALIGERANTES PARA LA CONSTRUCCIÓN. APLICACIÓN A SISTEMAS DE CONTROL DE RUIDO.

Degree: 2016, Universitat Politècnica de València

URL: http://hdl.handle.net/10251/59463

► [EN] The work presented here focuses on the study of the acoustic behavior of rigid structure granular materials derived from natural products. Lightening materials are… (more)

▼ [EN] The work presented here focuses on the study of the acoustic behavior of rigid structure granular materials derived from natural products. Lightening materials are employed in construction. Severals products are extracted directly from quarry, being processed in industrial treatment plants to obtain the required properties. These materials do not contribute to environmental pollution from the point of view of the product nature. Products as arlite and vermiculite are available in the market with different particle sizes. These materials have very interesting properties: they exhibit high porosity, withstand high temperatures, have advantages from an economic point of view and their density is low. These lightweight materials are used in applications as loose material for various purposes: gardening, filling landfills or thermal insulation, among other examples. However, porous granular products obtained from expanded clay aggregates or vermiculite in cement mortar open a wide field of possibilities: acoustic screens to reduce acoustic impact in public or residential areas, absorbent material seen or hidden for walls and ceilings, etc. The potential of these granular materials in construction is interesting as they allow formation of prefabricated panels with multiple aesthetic geometries obtained under formwork molds. In this thesis the use of such composites is proposed in order to increase the sound attenuation in industrial noise control devices, such as silencers used in energy production plants, combustion engines, ventilation systems and air conditioning. To do this, the evaluation of properties as well as acoustic and non-acoustic parameters is carried out of various particle sizes obtained with arlite and vermiculite and the acoustic absorption coefficient is also obtained. The high temperature resistance of the granular material enables their use in severals industrial applications, including those discussed above in the field of industrial noise control devices. The feasibility of the solutions examined and proposed in this PhD thesis as sound-absorbing material to use inside silencers is an aspect to consider and its application in this sector is studied. It is interesting to obtain a granular product with sufficient consistency. As it is shown in the work , the amount of cement used in the preparation of the mortar sets the grain size of the final product and is decisive for a lightweight strength material in practical applications. The influence of the dosing of raw materials in the preparation of the mixture is analyzed. This effect is very important in vermiculite. After an exhaustive process, five granular compounds (2 from arlite and 3 from vermiculite) with different grain size are analized and acoustically studied. Sound absorption coefficient and flow resistivity are experimentally measured. Other non-acoustic parameters such as porosity, tortuosity and pore size distribution were experimentally determined. The implementation of these parameters in a theoretical model to predict acoustic… Advisors/Committee Members: Denia Guzmán, Francisco David (advisor), Nadal Gisbert, Antonio Vicente (advisor).

Subjects/Keywords: Material granular; Arlita, vermiculita; Acústica; Atenuación sonora; Control de ruido; Silenciadores disipativos.

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APA (6^th Edition):

Esquerdo Lloret, T. V. (2016). DESARROLLO DE MODELOS DE COMPORTAMIENTO ACÚSTICO Y CARACTERIZACIÓN EXPERIMENTAL DE MATERIALES ELABORADOS CON ALIGERANTES PARA LA CONSTRUCCIÓN. APLICACIÓN A SISTEMAS DE CONTROL DE RUIDO. (Doctoral Dissertation). Universitat Politècnica de València. Retrieved from http://hdl.handle.net/10251/59463

Chicago Manual of Style (16^th Edition):

Esquerdo Lloret, Tomás Vicente. “DESARROLLO DE MODELOS DE COMPORTAMIENTO ACÚSTICO Y CARACTERIZACIÓN EXPERIMENTAL DE MATERIALES ELABORADOS CON ALIGERANTES PARA LA CONSTRUCCIÓN. APLICACIÓN A SISTEMAS DE CONTROL DE RUIDO. ” 2016. Doctoral Dissertation, Universitat Politècnica de València. Accessed April 13, 2021. http://hdl.handle.net/10251/59463.

MLA Handbook (7^th Edition):

Esquerdo Lloret, Tomás Vicente. “DESARROLLO DE MODELOS DE COMPORTAMIENTO ACÚSTICO Y CARACTERIZACIÓN EXPERIMENTAL DE MATERIALES ELABORADOS CON ALIGERANTES PARA LA CONSTRUCCIÓN. APLICACIÓN A SISTEMAS DE CONTROL DE RUIDO. ” 2016. Web. 13 Apr 2021.

Vancouver:

Esquerdo Lloret TV. DESARROLLO DE MODELOS DE COMPORTAMIENTO ACÚSTICO Y CARACTERIZACIÓN EXPERIMENTAL DE MATERIALES ELABORADOS CON ALIGERANTES PARA LA CONSTRUCCIÓN. APLICACIÓN A SISTEMAS DE CONTROL DE RUIDO. [Internet] [Doctoral dissertation]. Universitat Politècnica de València; 2016. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/10251/59463.

Council of Science Editors:

Esquerdo Lloret TV. DESARROLLO DE MODELOS DE COMPORTAMIENTO ACÚSTICO Y CARACTERIZACIÓN EXPERIMENTAL DE MATERIALES ELABORADOS CON ALIGERANTES PARA LA CONSTRUCCIÓN. APLICACIÓN A SISTEMAS DE CONTROL DE RUIDO. [Doctoral Dissertation]. Universitat Politècnica de València; 2016. Available from: http://hdl.handle.net/10251/59463

29. Hidalgo Signes, Carlos. APLICACIÓN AL ESTUDIO DE LA RESPUESTA MECÁNICA DE LA CAPA DE SUBBALASTO DE VÍAS FERROVIARIAS FORMADO POR UNA MEZCLA NO BITUMINOSA DE MATERIAL GRANULAR Y PARTÍCULAS PROCEDENTES DE NEUMÁTICOS FUERA DE USO.

Degree: 2017, Universitat Politècnica de València

URL: http://hdl.handle.net/10251/86140

► Scrap tyres are a solid waste material which has been generated in large quantities over the last decades. In Spain, between 2000 and 2014 the… (more)

▼ Scrap tyres are a solid waste material which has been generated in large quantities over the last decades. In Spain, between 2000 and 2014 the number of vehicles increased by 30% and a further 3.5% increment is expected for the next fifteen years. Likewise, the number of scrap tyres is also expected to rise within the same order of magnitude. Taking into account the big volume of waste generated, proper disposal and reutilisation management is required, ever more so as scrap tyres are non-biodegradable. Moreover, if simply stockpiled in landfills, further environmental damage may be produced in case of fire as the fumes thus generated carry harmful carcinogenic particles. In order to deal with this problem, a Royal Decree (RD 1481/2001) was approved in July 16, 2006 which completely forbidden landfilling of scrap tyres. Later the same year another Royal Decree (RD 1619/2005) was issued to establish scrap tyres management in Spain. This decree requires reutilisation and recycling plans to be elaborated so as to fully eliminate waste derived from scrap tyres. Nowadays, among the reutilisation options more demanded are tyre remoulding, construction of sport pitches, artificial grass and playpens, and as combustible for cement factories. On the other hand, only 1% of scrap tyres are reused in infrastructure construction. Taking profit of the latest transport plans approved by the European Union, which aim to promote more efficient and environmentally friendly transport means such as railways, this PhD thesis proposes a new and promising alternative: to use rubber particles from scrap tyres as construction material, in the form of unbounded rubber-aggregate mixtures for subballast layers under railway tracks. This option offers two noteworthy environmental advantages. On the one hand, large quantities of a rather problematic and harmful waste material may be reused. On the other hand, the new mixtures proposed help to improve the low resistance to fragmentation of calcareous aggregates, thus allowing the use of such materials in the construction of railway tracks. The objective of this research is to obtain the optimum rubber content for the new mixtures to fulfil all the requirements of subballast layers. Moreover, taking into account the elastic properties of rubber, the potential attenuation of the vibration generated by passing rolling stock is also assessed. As a complementary research, rubber-natural soil mixtures are studied as well so as to evaluate their viability as construction material for embankment cores.; El neumático fuera de uso es un residuo sólido que se está generando en grandes cantidades en las últimas décadas. En España, entre los años 2000 y 2014 el parque de vehículos se incrementó en un 30%, y se prevé un aumento del 3.5% para los próximos quince años. Estos datos ponen de manifiesto que el número de neumáticos fuera de uso se incrementará en el mismo orden. Dado el gran volumen de residuo generado, es necesario realizar una gestión de retirada y reutilización de este residuo, al tratarse de una… Advisors/Committee Members: Insa Franco, Ricardo (advisor).

Subjects/Keywords: subbalasto; neumáticos fuera de uso; mezclas material granular-caucho; atenuación de vibraciones.

11 more images…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hidalgo Signes, C. (2017). APLICACIÓN AL ESTUDIO DE LA RESPUESTA MECÁNICA DE LA CAPA DE SUBBALASTO DE VÍAS FERROVIARIAS FORMADO POR UNA MEZCLA NO BITUMINOSA DE MATERIAL GRANULAR Y PARTÍCULAS PROCEDENTES DE NEUMÁTICOS FUERA DE USO. (Doctoral Dissertation). Universitat Politècnica de València. Retrieved from http://hdl.handle.net/10251/86140

Chicago Manual of Style (16^th Edition):

Hidalgo Signes, Carlos. “APLICACIÓN AL ESTUDIO DE LA RESPUESTA MECÁNICA DE LA CAPA DE SUBBALASTO DE VÍAS FERROVIARIAS FORMADO POR UNA MEZCLA NO BITUMINOSA DE MATERIAL GRANULAR Y PARTÍCULAS PROCEDENTES DE NEUMÁTICOS FUERA DE USO. ” 2017. Doctoral Dissertation, Universitat Politècnica de València. Accessed April 13, 2021. http://hdl.handle.net/10251/86140.

MLA Handbook (7^th Edition):

Hidalgo Signes, Carlos. “APLICACIÓN AL ESTUDIO DE LA RESPUESTA MECÁNICA DE LA CAPA DE SUBBALASTO DE VÍAS FERROVIARIAS FORMADO POR UNA MEZCLA NO BITUMINOSA DE MATERIAL GRANULAR Y PARTÍCULAS PROCEDENTES DE NEUMÁTICOS FUERA DE USO. ” 2017. Web. 13 Apr 2021.

Vancouver:

Hidalgo Signes C. APLICACIÓN AL ESTUDIO DE LA RESPUESTA MECÁNICA DE LA CAPA DE SUBBALASTO DE VÍAS FERROVIARIAS FORMADO POR UNA MEZCLA NO BITUMINOSA DE MATERIAL GRANULAR Y PARTÍCULAS PROCEDENTES DE NEUMÁTICOS FUERA DE USO. [Internet] [Doctoral dissertation]. Universitat Politècnica de València; 2017. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/10251/86140.

Council of Science Editors:

Hidalgo Signes C. APLICACIÓN AL ESTUDIO DE LA RESPUESTA MECÁNICA DE LA CAPA DE SUBBALASTO DE VÍAS FERROVIARIAS FORMADO POR UNA MEZCLA NO BITUMINOSA DE MATERIAL GRANULAR Y PARTÍCULAS PROCEDENTES DE NEUMÁTICOS FUERA DE USO. [Doctoral Dissertation]. Universitat Politècnica de València; 2017. Available from: http://hdl.handle.net/10251/86140

University of Florida

30. Mishra, Nikhil Kailashnath. Effects of the Grain-To-Grain Contact Phenomenon on the Bulk Response of Granular Material.

Degree: PhD, Civil Engineering - Civil and Coastal Engineering, 2019, University of Florida

URL: https://ufdc.ufl.edu/UFE0056127

► The present dissertation outlines a solution procedure to tackle the engineering problems related to the granular materials, using a combined approach of laboratory measurements and… (more)

Subjects/Keywords: discrete-element-method – granular-material – normal-contact-stiffness – surface-roughness – tri-axial-test

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mishra, N. K. (2019). Effects of the Grain-To-Grain Contact Phenomenon on the Bulk Response of Granular Material. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0056127

Chicago Manual of Style (16^th Edition):

Mishra, Nikhil Kailashnath. “Effects of the Grain-To-Grain Contact Phenomenon on the Bulk Response of Granular Material.” 2019. Doctoral Dissertation, University of Florida. Accessed April 13, 2021. https://ufdc.ufl.edu/UFE0056127.

MLA Handbook (7^th Edition):

Mishra, Nikhil Kailashnath. “Effects of the Grain-To-Grain Contact Phenomenon on the Bulk Response of Granular Material.” 2019. Web. 13 Apr 2021.

Vancouver:

Mishra NK. Effects of the Grain-To-Grain Contact Phenomenon on the Bulk Response of Granular Material. [Internet] [Doctoral dissertation]. University of Florida; 2019. [cited 2021 Apr 13]. Available from: https://ufdc.ufl.edu/UFE0056127.

Council of Science Editors:

Mishra NK. Effects of the Grain-To-Grain Contact Phenomenon on the Bulk Response of Granular Material. [Doctoral Dissertation]. University of Florida; 2019. Available from: https://ufdc.ufl.edu/UFE0056127

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Open Access Theses and Dissertations