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You searched for subject:(Pore pressure measurements). Showing records 1 – 2 of 2 total matches.

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1. Metallinos, Anastasios. Υδροδυναμικές συνθήκες σε ύφαλο διαπερατό κυματοθραύστη λόγω θαλασσίων κυματισμών.

Degree: 2016, National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ)

Submerged breakwaters (SB), often rubble mound structures, are frequently built along the coast toreduce the impact of waves and currents affecting the shoreline, mainly by induced wave breaking, andto prevent beach erosion. This type of low-crested breakwaters enhances its acceptability due to itsenvironmental advantages mainly in easing water circulation near the surface reducing thus anyadverse impact on water quality, while ensuring the aesthetic value of the coastal landscape. Theseconsiderations demonstrate that the introduction of SB for protection of the coastal zone is a promisingfield of research. A solid understanding of the interaction between water waves and SB is thus vital,especially in SB with relatively steep slopes which are more commonly used.Only a little is known on how marine organisms respond to the SB’s presence. Hydrodynamicconditions, in the body of the structure, are known to be of significance for the habitation of marine lifewithin and around the barrier. Indeed, in assessing the ecological impact of such a structure,knowledge of hydrodynamic field in the interior of the structure is of prime importance. The main targetfor technical applications is trying to combine the structure’s technical efficiency with ecologicalrequirements. A key parameter to assess the shelter SB provide to the local habitats is the waterparticle velocity and pore pressure in the interior of the structure.In this study, in order to extent the applicability of a fully dispersive and highly nonlinear 2DHBoussinesq-type model presented by Chondros and Memos (2014), a depth-averaged Darcy equation,extended to include 2DH Forchheimer terms, calculating the flow within the porous medium followingthe approach of Cruz et al. (1997) and Avgeris et al. (2004). The modified Boussinesq-type model,referred to as mCM14 hereinafter, incorporates extra 2DH terms accounting for the interaction betweenthe waves over the structure and the flow within the porous breakwater. Also, a major point of thisstudy is to go a step further from the depth averaged velocity of the Boussinesq model in the interior ofthe structure and to present a method, that is not too difficult numerically, for estimating the distributionof horizontal particle velocities in two directions and respectively as well as pore pressures in theinterior of a submerged permeable structure. A velocity profile, based on a distribution of the nonlinearwave theory (Dingemans, 1997), is fitted to the numerically predicted depth-integrated velocity given bymCM14 in the SB interior. Further, another method based in the full form of Darcy-Forchheimerequation is reworked to obtain the pore pressure as a function of the velocities quantities.Due to the small number of experiments including wave propagation over SB with steep slopes and extreme porosity and practically the lack of laboratory measurements of velocities and pressures in theinterior of the structure, an adequate number of 1DH and 2DH experiments were conducted during thepresent research. Specifically, for the sake of…

Subjects/Keywords: Αριθμητικό μοντέλο τύπου Boussinesq; Εργαστηριακές μετρήσεις 1DH & 2DH; Διαπερατές κατασκευές; Κατανομή πιέσεων; Κατανομή ταχυτήτων; Μετρήσεις ανύψωσης/ταπείνωσης στάθμης ελεύθερης επιφάνειας; Μετρήσεις πιέσεων; Μετρήσεις ταχυτήτων; Μονοχρωματικοί κυματισμοί; Παράκτιες κατασκευές; Περιβαλλοντική μηχανική; Ροή Forchheimer; Σύνθετοι κυματισμοί; Ύφαλοι κυματοθράυστες; Boussinesq-type model; Coastal structures; Ecological engineering; Forchheimer flow; Jonswap waveς; Laboratory experiments 1DH & 2DH; Permeable structures; Pore pressure measurements; Porepressure distribution; Porous structures; Regular waves; Submerged breakwaters; Surface elevation measurements; Velocity distribution; Velocity measurements; Wave kinematics

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

APA (6th Edition):

Metallinos, A. (2016). Υδροδυναμικές συνθήκες σε ύφαλο διαπερατό κυματοθραύστη λόγω θαλασσίων κυματισμών. (Thesis). National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ). Retrieved from http://hdl.handle.net/10442/hedi/44014

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

Chicago Manual of Style (16th Edition):

Metallinos, Anastasios. “Υδροδυναμικές συνθήκες σε ύφαλο διαπερατό κυματοθραύστη λόγω θαλασσίων κυματισμών.” 2016. Thesis, National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ). Accessed July 09, 2020. http://hdl.handle.net/10442/hedi/44014.

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

MLA Handbook (7th Edition):

Metallinos, Anastasios. “Υδροδυναμικές συνθήκες σε ύφαλο διαπερατό κυματοθραύστη λόγω θαλασσίων κυματισμών.” 2016. Web. 09 Jul 2020.

Vancouver:

Metallinos A. Υδροδυναμικές συνθήκες σε ύφαλο διαπερατό κυματοθραύστη λόγω θαλασσίων κυματισμών. [Internet] [Thesis]. National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ); 2016. [cited 2020 Jul 09]. Available from: http://hdl.handle.net/10442/hedi/44014.

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

Council of Science Editors:

Metallinos A. Υδροδυναμικές συνθήκες σε ύφαλο διαπερατό κυματοθραύστη λόγω θαλασσίων κυματισμών. [Thesis]. National Technical University of Athens (NTUA); Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ); 2016. Available from: http://hdl.handle.net/10442/hedi/44014

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

2. Tsaparas, Ilias. Field measurements and numerical modelling of infiltration and matric suctions within slopes.

Degree: 2002, Institutes outside Greece; Ιδρύματα Εξωτερικού

This work presents an analysis of the matric suction and seepage conditions within two residual soil slopes in Singapore. The analysis is based on field measurements and on numerical modelling using a finite element software capable of modelling transient unsaturated flow. The field measurements consist of rainfall data, runoff data and matric suctions changes during infiltration at several depths and locations on the two slopes. The field measurements indicated that the infiltration mechanism is complex and that matric suctions are affected not only from rainfall pattern but also on the initial conditions within two slopes. The objective of the numerical modelling of the field measurements was to couple all the available field information into one complete model. The numerical analysis reflects the complexity of the infiltration mechanism and confirms that infiltration is controlled by the initial conditions within a slope. It was seen that a slope appears to have a limiting capacity for how much rainfall water can become infiltration, regardless of how high or low the permability value of the surface may be. This was explained in terms of hydraulic gradient. That means that large amounts of rainfall do not automatically lead to high infiltration.

Η διατριβή παρέχει μία ανάλυση των αρνητικών πιέσεων πόρων και των συνθηκών ροής νερού σε δύο πρανή από πλήρως αποσαθρωμένο έδαφος στη Σιγκαπούρη. Η ανάλυση βασίζεται σε μετρήσεις υπαίθρου ενός χρόνου και σε αριθμητική ανάλυση με χρήση πεπερασμένων στοιχείων. Οι μετρήσεις υπαίθρου αποτελούνται από μετρήσεις βροχής, απορροής και μεταβολής των αρνητικών πιέσεων πόρων σε διάφορα σημεία και βάθη των πρανών. Οι μετρήσεις δείχνουν ότι ο μηχανισμός εισροής νερού είναι πολύπλοκος και ότι οι πιέσεις πόρων μεταβάλλονται τόσο από την ποσότητα και ένταση της βροχής όσο και από τις αρχικές συνθήκες. Ο σκοπός της αριθμητικής ανάλυσης ήταν να συνδυάσει όλες τις πληροφορίες υπαίθρου σε ένα αριθμητικό μοντέλο. Η ανάλυση περιγράφει τον πολύπλοκο μηχανισμό εισροής νερού στο πρανές και επαληθεύει τον κύριο λόγο που έχουν οι αρχικές συνθήκες. Από την ανάλυση φάνηκε ότι το πρανές έχει περιορισμένη ικανότητα απορρόφησης νερού ανεξάρτητα του πόσο αυξημένη ή μειωμένη είναι η υδατοπερατότητα στην επιφάνεια του εδάφους. Το φαινόμενο εξηγείται με την υδραυλική ακτίνα και τις μεταβολές της με το χρόνο. Συμπερασματικά, μεγάλες ποσότητες νερού δεν οδηγούν αυτόματα σε μεγάλη εισροή.

Subjects/Keywords: Ευστάθεια πρανών; Αρνητικές πιέσεις πόρων; Εισροή βρόχινου νερού; Πλήρως αποσαθρωμένα εδάφη; Μετρήσεις υπαίθρου; Αριθμητική ανάλυση με πεπερασμένα στοιχεία; Υδατοπερατότητα; Ακόρεστα εδαφικά πρανή; Slope stability; Negative pore-water pressure-matric suctions; Infiltration of rainfall water; Residual soils; Field measurements; Numerical analysis with finite elements; Permeability to water; Unsaturated soil slopes

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

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

APA (6th Edition):

Tsaparas, I. (2002). Field measurements and numerical modelling of infiltration and matric suctions within slopes. (Thesis). Institutes outside Greece; Ιδρύματα Εξωτερικού. Retrieved from http://hdl.handle.net/10442/hedi/22825

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

Chicago Manual of Style (16th Edition):

Tsaparas, Ilias. “Field measurements and numerical modelling of infiltration and matric suctions within slopes.” 2002. Thesis, Institutes outside Greece; Ιδρύματα Εξωτερικού. Accessed July 09, 2020. http://hdl.handle.net/10442/hedi/22825.

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

MLA Handbook (7th Edition):

Tsaparas, Ilias. “Field measurements and numerical modelling of infiltration and matric suctions within slopes.” 2002. Web. 09 Jul 2020.

Vancouver:

Tsaparas I. Field measurements and numerical modelling of infiltration and matric suctions within slopes. [Internet] [Thesis]. Institutes outside Greece; Ιδρύματα Εξωτερικού; 2002. [cited 2020 Jul 09]. Available from: http://hdl.handle.net/10442/hedi/22825.

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

Council of Science Editors:

Tsaparas I. Field measurements and numerical modelling of infiltration and matric suctions within slopes. [Thesis]. Institutes outside Greece; Ιδρύματα Εξωτερικού; 2002. Available from: http://hdl.handle.net/10442/hedi/22825

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

.