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Taherzadeh, Reza. "Seismic soil-pile group-structure interaction." Châtenay-Malabry, Ecole centrale de Paris, 2008. http://www.theses.fr/2008ECAP1096.
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Si la prise en compte de l'interaction sol-structure peut être abordée de façon relativement simple dans la plupart des fondations superficielles, il n'en est pas de même pour des groupes de pieux. Les principales difficultés rencontrées sont liées à la complexité et à la taille du modèle numérique nécessaire à l’analyse détaillée. Cette thèse porte sur la modélisation de l’interaction dynamique sol-structure dans le cas particulier des fondations comportant un grand nombre de pieux. Ce travail consiste à faire des modélisations avancées en utilisant un couplage entre le logiciel MISS3D d’éléments de frontière pour des milieux élastiques stratifiés et la toolbox matlab d’éléments finis SDT pour la modélisation des fondations et des structures. Après avoir validé la modélisation à partir de solutions de la littérature, les principaux paramètres gouvernant l’impédance de ces fondations ont été mis en évidence. Les modèles simplifiés de ces impédances ont ensuite été développés dans le cas de pieux flottants ou de pieux encastrés dans un bedrock. Des paramètres de ces modèles simplifiés ont été déterminés par des analyses statistiques fondées sur une base étendue de modèles numériques couvrant une large gamme de situations pratiques. Ces modèles approchés ont été validés sur des cas particuliers, puis différents spectres de réponse modifiés par la prise en compte de l’interaction sol-structure ont été proposésDespite the significant progress in simple engineering design of surface footing with considering the soil-structure interaction (SSI), there is still a need of the same procedure for the pile group foundation. The main approach to solve this strongly coupled problem is the use of full numerical models, taking into account the soil and the piles with equal rigor. This is however a computationally very demanding approach, in particular for large numbers of piles. The originality of this thesis is using an advanced numerical method with coupling the existing software MISS3D based on boundary element (BE), green's function for the stratified infinite visco-elastic soil and the matlab toolbox SDT based on finite element (FE) method to modeling the foundation and the superstructure. After the validation of this numerical approach with the other numerical results published in the literature, the leading parameters affecting the impedance and the kinematic interaction have been identified. Simple formulations have then been derived for the dynamic stiffness matrices of pile groups foundation subjected to horizontal and rocking dynamic loads for both floating piles in homogeneous half-space and end-bearing piles. These formulations were found using a large data base of impedance matrix computed by numerical FE-BE model. These simple approaches have been validated in a practical case. A modified spectral response is then proposed with considering the soil-structure interaction effect
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Dewsbury, Jonathan J. "Numerical modelling of soil-pile-structure interaction." Thesis, University of Southampton, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.582152.
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Soil-pile-structure interaction analysis is the simultaneous consideration of the structural frame, pile foundations, and the soil forming the founding material. Failure to consider soil-pile-structure interaction in design will lead to a poor prediction of load distribution within the structure. A poor prediction of load distribution will cause the structure to deform under loads that have not been calculated for. This may result in the structure cracking or the overstressing of columns. If the actual load distribution significantly differs from that designed for, the factor of safety on structural elements may be substantially decreased. Despite the importance, there are currently no studies quantifying the effect of soil-pile-structure interaction for simple office structures. As a result the effects of soil-pile-structure interaction are often deemed unimportant, and ignored in the design of simple structures. Numerical methods are often relied upon to consider soil-pile-structure interaction for complex structures, such as tall towers. However in their current form they are limited because the meshes required for analysis, especially when in three dimensions, are difficult to verify, and take a long time to set up and run. Therefore this thesis proposes a meshing method within the framework of the finite element method that allows large, complex, and non-symmetrical pile foundation layouts to be meshed in a manner that is quick, can be easily checked, and significantly reduces the analysis run time. Application of the meshing method to an office structure (recently designed for the 2012 Olympic Games) has allowed the effects of soil-pile-structure interaction to be quantified. The subsequent normalisation of the results provides a method for assessing when it is necessary to consider soil- pile-structure interaction in future design. Comparison between the monitored performance of 'The Landmark' (a 330m tower founded on a piled raft) and numerical predictions have demonstrated the importance of correct ground stiffness selection for achieving accurate predictions of piled raft settlement, and load distribution. The role of single pile load tests and in situ testing for ground stiffness selection for piled raft design has also been assessed
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Balendra, Surendran. "Numerical modeling of dynamic soil-pile-structure interaction." Online access for everyone, 2005. http://www.dissertations.wsu.edu/Thesis/Fall2005/s%5Fbalendra%5F120705.pdf.
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Strand, Tommy, and Johannes Severin. "Soil-Structure Interaction of Pile Groups for High-Speed Railway Bridges." Thesis, KTH, Bro- och stålbyggnad, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231413.
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Pérez-Herreros, Jesús. "Dynamic soil-structure interaction of pile foundations : experimental and numerical study." Thesis, Ecole centrale de Nantes, 2020. http://www.theses.fr/2020ECDN0002.
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La réponse dynamique d’une structure supportée par des fondations profondes constitue un problème complexe d’Interaction Sol-Structure (ISS). Sous chargement sismique, les pieux sont soumis à la sollicitation imposée par le sol (interaction cinématique) et aux forces d’inertie transmises par la superstructure (interaction inertielle). Le dimensionnement des fondations profondes soumises à des sollicitations sismiques est souvent réalisé au moyen de méthodes conservatrices visant à assurer que les fondations ne soient pas endommagées. La plupart de ces méthodes considèrent le comportement de la fondation élastique linéaire et par conséquent la capacité de la fondation à dissiper de l’énergie du fait des mécanismes non-linéaires est négligée. Cette approche était justifiée dans le passé en raison du manque d’informations sur le comportement non-linéaire des fondations et de l’absence d’outils numériques adaptés. De telles limitations deviennent de plus en plus obsolètes, puisqu’un nombre pertinent de résultats expérimentaux et numériques sont maintenant disponibles, ainsi que de nouvelles méthodes de conception (Pecker et al. 2012). Dans cette thèse, le comportement des pieux isolés et des groupes de pieux sous chargement sismique est étudié avec une approche couplant l’expérimental et le numérique. Des essais dynamiques en centrifugeuse sont effectués avec un sol stratifié, plusieurs configurations de fondations et une série de séismes et sollicitations sinusoïdales. Des calculs non-linéaires aux éléments finis sont également effectués et comparés aux résultats expérimentaux afin d’étudier la capacité des modèles numériques à reproduire de manière satisfaisante la réponse non-linéaire des fondations. Un nouveau macroélément pour les groupes de pieux sous chargement sismique est proposé et validé numériquement. Le macroélément permet de prendre en compte les effets de groupe et leur variation avec la fréquence de sollicitation (interaction pieu-sol-pieu) ainsi que la non-linéarité développée dans le système. Le nouveau macroélément est enfin utilisé pour effectuer une analyse dynamique incrémentale (IDA) du pylône centrale d’un pont à haubansThe dynamic response of a structure supported by pile foundations is a complex Soil-Structure Interaction (SSI) problem. Under earthquake loading, the piles are subjected to loadings due to the deformation imposed by the soil (kinematic interaction) and to the inertial forces transmitted by the superstructure (inertial interaction). The design of deep foundations under seismic loadings is often carried out by means of conservative methods that aim to assure zero damage of the foundation. Most of these methods consider the behavior of the foundation as linear elastic. As a result, the capability of the foundation to dissipate energy during seismic loading due to nonlinear mechanisms is neglected. This approach was justified in the past due to the lack of information about the nonlinear behavior of foundations and the absence of adapted numerical tools. Such limitations are becoming more and more obsolete, as a relevant number of experimental and numerical results are now available as well as new design methods (Pecker et al. 2012). In this Ph.D, the behavior of single piles and pile groups under seismic loading is studied using both experiments and finite element calculations. Dynamic centrifuge tests are carried out with a multilayered soil profile, several foundation configurations and a series of earthquakes and sinusoidal base shakings. Nonlinear finite element calculations are also performed and compared to experimental results to investigate the ability of current computational models to satisfactorily reproduce the nonlinear response of foundations. A novel macroelement for pile group foundations under seismic loading is developed and numerically validated. It allows taking into account the group effects and their variation with the loading frequency (pile-soil-pile interaction) as well as the nonlinearity developed in the system. Finally, the macroelement model for pile groups is used to perform an Incremental Dynamic Analysis (IDA) of the main pylon of a cable-stayed bridge
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Ahmed, Mahmoud Nasser Hussien. "Effects of Nonlinear Soil-Structure Interaction on Lateral Behavior of Pile Foundations." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/151949.
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Al-Khazaali, Mohammed. "Soil-Pile, Pile Group Foundations and Pipeline Systems Interaction Behavior Extending Saturated and Unsaturated Soil Mechanics." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38843.
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Rapid growth in population along with positive trends in global economy over the past several decades has significantly contributed to an increased demand for various infrastructure needs worldwide. For this reason, the focus of this thesis has been directed towards extending the mechanics of unsaturated soils, which is an emerging geotechnical engineering field to investigate the behavior of two key infrastructure systems, namely pile foundations and energy pipeline systems. The mechanism of soil-pile foundations and soil-pipeline systems interaction behavior has several similarities.
Both these infrastructure facilities require comprehensive understanding of the soil-structure interaction mechanism. Reliable estimation of mechanical properties of both the soil and the soil-structure interface is required for the rational interpretation the load-displacement behavior of pile foundations and pipeline systems. Currently, the design of systems is predominantly based on design codes and guidelines that use empirical procedures or employ the principles of saturated soil mechanics. In many scenarios, pile foundations extend either totally or partly in unsaturated soils as the groundwater table level in many regions is at a greater depth. Such scenarios are commonly encountered in semi-arid and arid regions of the world. In addition, pipeline systems are typically buried at shallow depths in unsaturated soil strata, which are susceptible to wetting and drying, freezing and thawing cycles or both, due to seasonal environmental changes. Capillary stress or matric suction in the unsaturated zone increases the effective stress contribution towards the shear strength and stiffness of soil and soil-structure interface. Extending saturated soil mechanics to design or analyze such structures may lead to erroneous estimation of pile foundation carrying capacity or loads transferred on pipeline body from the surrounding unsaturated soil.
Experimental, analytical and numerical investigations were undertaken to study the behavior of single pile, pile group, and pipeline systems in saturated and unsaturated sands under static loading. The experimental program includes 40 single model pile and 2×2 pile group, and six prototype pipeline tests under saturated and unsaturated condition. The results of the experimental studies suggest that matric suction has significant contribution towards the mechanical behavior of both pile foundation and pipeline system.
The axial load carrying capacity of single pile and pile group increased approximately 2 to 2.5 times and the settlement reduced significantly compared to saturated condition. The influence of matric suction towards a single pile is significantly different in comparison to pile group behavior. The cumulative influence of matric suction and stress overlap of pile group behavior in sandy soils result in erroneous estimation of pile group capacity, if principles of saturated soil mechanics are extended. Group action plays major role in changing the moisture regime under the pile group leading to incompatible stress state condition in comparison to single pile behavior.
On the other hand, the peak axial load on the pipe is almost 2.5 folds greater in unsaturated sand that undergoes much less displacement in comparison to saturated condition. Such an increase in the external axial forces may jeopardize the integrity of energy pipeline systems and requires careful reevaluation of existing design models extending the principles of unsaturated soil mechanics. Two analytical design models to estimate the axial force exerted on pipeline body were proposed. The proposed models take account of matric suction effect and soil dilatancy and provide smooth transition from unsaturated to saturated condition. These models were developed since measurement of the unsaturated soil and interface shear strength and stiffness properties need extensive equipment that require services of trained professional, which are expensive and time consuming. The models utilize the saturated soil shear strength parameters and soil-water characteristic curve (SWCC) to predict the mechanical behavior of the structure in saturated and unsaturated cohesionless soils. The prototype pipeline experimental results were used to verify the proposed models. The predicted axial force on pipeline using the proposed models agrees well with the measured behavior under both saturated and unsaturated conditions.
Moreover, numerical techniques were proposed to investigate the behavior of pile foundation and pipeline system in saturated and unsaturated sand. The proposed methodology can be used with different commercially available software programs. Two finite element analysis programs were used in this study; namely, PLAXIS 2D (2012) to simulate soil-pile foundation behavior and SIGMA/W (2012) to simulate soil-pipeline system behavior. The proposed techniques require the information of unsaturated shear strength and stiffness, which can be derived from saturated soil properties and the SWCC. The model was verified using pile and pipeline test results from this study and other research studies from the published literature. There is a good agreement between the measured behavior and the predicted behavior for both the saturated and unsaturated conditions. The methodology was further extended to investigate the behavior of rigid and flexible pipelines buried in Indian Head till (IHT) during nearby soil excavation activity. The simulation results suggest that excavation can be extended safely without excessive deformation to several meters without the need for supporting system under unsaturated condition.
The studies summarized in the thesis provide evidence that the principles of saturated soil mechanics underestimate the pile foundations carrying capacity as well as the axial force exerted on pipelines in unsaturated soils. Such approaches lead to both uneconomical pile foundation and unsafe pipeline systems designs. For this reason, the pile and pile group carrying capacity and pipeline axial force should be estimated taking into account the influence of matric suction as well as the dilatancy of the compacted sand. The experimental studies, testing techniques along with the analyses of test results and the proposed analytical and numerical models are useful for better understanding the pile foundation and buried pipeline behaviors under both saturated and unsaturated conditions. The proposed analytical and finite element models are promising for applying the mechanics of unsaturated soils into conventional geotechnical engineering practice using simple methods.
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Bransby, Mark Fraser. "Piled foundations adjacent to surcharge loads." Thesis, University of Cambridge, 1995. https://www.repository.cam.ac.uk/handle/1810/251968.
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Rahmani, Amin. "Three-dimensional nonlinear analysis of dynamic soil-pile-structure interaction for bridge systems under earthquake shakings." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/51269.
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Bridge designers have adopted simple approximate methods to take into account soil-structure-interaction (SSI) in dynamic analysis of bridge systems. The most popular one is the substructuring method in which the response of the foundation soil and its interaction with the pile foundation and the abutment system are represented by a set of one-dimensional springs and dashpots. While this method has been widely used in practice, it has never been validated by comparing the results with those obtained from full-scale analyses. This thesis aims to evaluate the substructuring method and to quantify the level of associated errors for the use in bridge engineering. To this end, the baseline data required for the evaluation process is provided by full-scale nonlinear dynamic analysis of the bridge systems subjected to earthquake shaking using continuum modeling method. This involves detailed modeling of the foundation soil, pile foundations, abutment system, and the whole bridge structure. Three representative bridge systems with two, three, and nine spans are simulated. In all models, nonlinear hysteretic response of the foundation soil and the bridge piers are accounted for in the analyses using advanced constitutive models. The numerical model of the bridge is validated by simulating the seismic response of the Meloland Road Overpass for which extensive measured data exist over past earthquake events. Subsequently each one of the three bridge systems is also simulated using the substructuring method. Comparing the obtained results with the baseline data indicates that the substructure model may not be sufficiently reliable in predicting the bridge response. In particular the method is shown to misrepresent the spectral responses of the bridge, pier deflections, shear forces and bending moments induced at the pier base, and longitudinal and transverse forces induced to the abutments. The substructuring method is shown to suffer from several fundamental drawbacks that cannot be simply resolved. Using the recent advances in constitutive modeling of geotechnical and structural materials, and in computational tools and high-performance parallel computing, this thesis shows that large-scale continuum models can gradually become a powerful and significantly more reliable alternative for proper modeling of seismic SSI in bridge engineering.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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Varun. "A non-linear dynamic macroelement for soil structure interaction analyses of piles in liquefiable sites." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34718.
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A macroelement is developed for soil-structure interaction analyses of piles in liquefiable soils, which captures efficiently the fundamental mechanisms of saturated granular soil behavior. The mechanical model comprises a nonlinear Winkler-type model that accounts for soil resistance acting along the circumference of the pile, and a coupled viscous damper that simulates changes in radiation damping with increasing material non-linearity. Three-dimensional (3D) finite element (FE) simulations are conducted for a pile in radially homogeneous soil to identify the critical parameters governing the response. The identified parameters, i.e., hydraulic conductivity, loading rate of dynamic loading, dilation angle and liquefaction potential are then expressed in dimensionless form.
Next, the macroelement parameters are calibrated as a function of the soil properties and the effective stress. A semi-empirical approach that accounts for the effects of soil-structure interaction on pore pressure generation in the vicinity of pile is used to detect the onset of liquefaction. The predictions are compared with field data obtained using blast induced liquefaction and centrifuge tests and found to be in good agreement.
Finally, the macroelement formulation is extended to account for coupling in both lateral directions. FEM simulations indicate that response assuming no coupling between the two horizontal directions for biaxial loading tends to overestimate the soil resistance and fails to capture features like 'apparent negative stiffness', 'strain hardening' and 'rounded corners'.
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Theland, Freddie. "Prediction and experimental validation of dynamic soil-structure interaction of an end-bearing pile foundation in soft clay." Licentiate thesis, KTH, Bro- och stålbyggnad, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291021.
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In the built environment, human activities such as railway and road traffic, constructionworks or industrial manufacturing can give rise to ground borne vibrations. Such vibrations become a concern in urban areas as they can cause human discomfort or disruption of vibration sensitive equipment in buildings. In Sweden, geological formations of soft clay soils overlying till and a high quality bedrock are encountered in densely populated areas, which are soil conditions that are prone to high levels of ground borne vibrations. Under such soil conditions, end-bearing piles are often used in the design of building foundations. The dynamic response of a building is governed by the interaction between the soil and the foundation. It is therefore essential that models used for vibration predictions are able to capture the dynamic soil-structure interaction of pile foundations. The purpose of this thesis is to experimentally and numerically investigate dynamic soil-structure interaction of an end-bearing pile group in clay by constructing a test foundation of realistic dimensions. The small-strain properties in a shallow clay deposit are estimated using different site investigation and laboratory methods. The results are synthesised into a representative soil model to compute the free-field surface response, which is validated with vibration measurements performed at the site. It is found that detailed information regarding material damping in the clay and the topmost soil layer both have a profound influence on the predicted surface response, especially with an increasing distance from the source. Dynamic impedances of four end-bearing concrete piles driven at the site are measured. Pile-soil-pile interaction is investigated by measuring the response of the neighbour piles when one of the piles in the group is excited. The square pile group is subsequently joined in a concrete cap and measurements of the impedances of the pilegroup and acceleration measurements within the piles at depth are performed. A numerical model based on the identified soil properties is implemented and validated by the measurements. A good agreement between the predicted and measured responses and impedances of the pile group foundation is found, establishing confidence in the ability to predict the dynamic characteristics of end-bearing pile foundations under the studied soil conditions.Mänsklig verksamhet i urbana miljöer så som väg- och järnvägstrafik, byggnation eller maskindrift inom industri kan ge upphov till vibrationer som sprider sig via marken i närområdet. Dessa vibrationer kan ge upphov till kännbara vibrationer eller påverka vibrationskänslig utrustning i byggnader. I Sverige förekommer ofta mjuka lerjordar ovanpå berg, och inte sällan i tätbebyggda områden. Under sådana jordförhållanden används ofta spetsbärande pålar för grundläggning av byggnader. Det dynamiska verkningssättet för byggnader är beroende av interaktionen mellan jorden och byggnadens grund. Det är därför viktigt att modeller som används för vibrationsanalys i byggnader kan beskriva denna interaktion mellan jord och byggnadsfundament. Syftet med denna avhandling är att experimentellt och via numeriska modeller studera dynamisk jord-struktur-interaktion av ett spetsbärande pålfundament i lera. Jordensmekaniska egenskaper vid små töjningar utvärderas för en lerjord som är avsatt på morän och berg genom både fältförsök och laboratorieanalyser av prover. Informationen kombineras för att konstruera en lagerförd jordmodell av platsen för att beräkna jordens dynamiska respons till följd av en punktlast. Modellen valideras med vibrationsmätningar som utförts på platsen. Studien visar att detaljerad information angående lerans materialdämpning och de mekaniska egenskaperna av jordens översta lager har en stor inverkan på förutsägelser av jordens dynamiska respons vid ytan, speciellt vid stora avstånd från vibrationskällan. Experimentella tester utförs för att mäta dynamiska impedanser av fyra slagna spetsbärande betongpålar. Interaktionen mellan pålarna utvärderas genom att utföra mätningarav de omgivande pålarnas respons till följd av excitering av en påle. Pålgruppen sammanfogas därefter i ett betongfundament och impedanserna samt accelerationer inuti pålarna uppmäts. En numerisk modell baserad på de identifierade mekaniska egenskaperna av jorden upprättas och valideras genom mätningarna. De numeriska resultaten är i god överensstämmelse med de uppmätta vilket styrker användningen av numeriska modeller för att förutsäga interaktionen mellan jord och spetsbärandepålar under de studerade jordförhållandena.
QC 20210302
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Al-Younis, Mohamad Jawad K. Essa. "Effect of Soil-Structure Interaction on the Behavior of Offshore Piles Embedded in Nonlinear Porous Media." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/283608.
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Pile foundations that support offshore structures are required to resist not only static loading, but also dynamic loading from waves, wind and earthquakes. The purpose of this study is to gain a better understanding of the behavior of offshore piles under cyclic or dynamic loading using the finite element approach. To achieve this goal, an appropriate constitutive model is required to simulate the behavior of soils and interfaces. The DSC constitutive model is developed for saturated interfaces to study the behavior under severe shear deformation at the soil-pile interface. Monotonic and cyclic simple shear experiments are conducted on Ottawa sand-steel interfaces under drained and undrained conditions using the Cyclic-Multi-Degree-of-Freedom shear device with porewater pressure measurement (CYMDOF-P). The effect of various parameters such as normal stress, surface roughness of steel, type of loading, and the amplitude and frequency of the applied displacement in two-way cyclic loading are investigated. The data from the simple shear tests on saturated interfaces are used to calculate the parameters in the DSC model. The resulting parameters are then used to verify the DSC model by back predicting tests from which parameters are determined and independent tests that are not used in parameters determination. The model predictions, in general, were found to provide a highly satisfactory correlation with the observations. In the context of DSC, the concept of critical disturbance is developed to identify initiation of liquefaction in saturated Ottawa sand-steel interfaces. This method is based on using microstructural changes in material as an indication of liquefaction identification. The finite element method, along with DSC constitutive model, is used to investigate the response of offshore piles to dynamic loading. These include cyclic loading of axially loaded instrumented pile in clay and full-scale laterally loaded pile in sand. The DSC model is used to model the nonlinear behavior of saturated soils and interfaces. A nonlinear dynamic finite element program DSC-DYN2D based on the DSC modeling approach and the theory of nonlinear porous media is used for this purpose. Results from numerical solutions are compared with field measurements. Strong agreement between numerical predictions and field measurements are an indication of the ability to solve challenging soil-structure interaction problems.Based on the results of this research, it can be stated that the finite element-DSC model simulation allows realistic prediction of complex dynamic offshore pile-soil interaction problems, and is capable of characterizing behavior of saturated soils and interfaces involving liquefaction.
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Yuksekol, Umit Taner. "A Simple Assessment Of Lateral Pier Response Of Standard Highway Bridges On Pile Foundations." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608135/index.pdf.
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Group of piles are widely used deep foundation systems to resist lateral and vertical loads. Seismic and static performance of pile groups mostly depend on soil type, pile spacing and pier rigidity.
Not many pile lateral load tests have been performed due to high costs. Advanced and complex analytical methods were developed over the years to assess nonlinear lateral pile response. This research is conducted aiming at developing a practical analysis method to verify the lateral performance of pile groups and its effect on overall response of bridge utilizing the available pile lateral load test data. Empirical constants derived from evaluation of lateral load tests are used in a simple formulation to define the nonlinear behavior of the pile-soil system. An analysis guideline is established to model the nonlinear soil-bridge interaction by the help of a general purpose structural analysis program comprising recommendations for various cases. Results of the proposed method is compared to the results of industry accepted advanced methods using response spectrum and nonlinear time history analyses to assess the suitability of this new application. According to the analysis results, proposed simple method can be used as an effective analysis tool for the determination of response of the superstructure.
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Ullberg, Mårten. "Development of a Parallel Finite-element Tool for Dynamic Soil-structure Interaction : A Preliminary Case Study on the Dynamic Stiffness of a Vertical Pile." Thesis, KTH, Bro- och stålbyggnad, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99381.
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This thesis has two major goals; first to develop scalable scripts for steady-state analysis, then to perform a case study on the dynamic properties of a vertical pile. The scripts are based on the numerical library PETSc for parallel linear algebra. This opens up the opportunity to use the scripts to solve large-scale models on supercomputers. The performance of the scripts are verified against problems with analytical solutions and the commercial software ABAQUS. The case study compares the numerical results with those obtained from an approximate solution. The results from this thesis are verified scripts that can find a steady-state solution for linear-elastic isotropic solids on supercomputers. The case study has shown differences between numerical and semi-analytical solutions for a vertical pile. The dynamic stiffness show differences within reasonable limits but the equivalent viscous damping show larger differences. This is believed to come from the material damping in the soil that has been excluded from the approximate solution. These two results make it possible for further case studies on typical three-dimensional problems, that result in large-scale models, such as the dynamic properties of a slanted pile or pile-groups. The scripts can easily be expanded and used for other interesting research projects and this is the major outcome of from this thesis.
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Shafieezadeh, Abdollah. "Seismic vulnerability assessment of wharf structures." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41203.
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Serving as critical gateways for international trade, seaports are pivotal elements in transportation networks. Any disruption in the activities of port infrastructures may lead to significant losses from secondary economic effects, and can hamper the response and recovery efforts following a natural disaster. Particularly poignant examples which revealed the significance of port operations were the 1995 Kobe earthquake and 2010 Haiti earthquake in which liquefaction and lateral spreading of embankments imposed severe damage to both structural and non-structural components of ports.
Since container wharf structures are responsible for loading and unloading of cargo, it is essential to understand the performance of these structures during earthquakes. Although previous studies have provided insight into some aspects of the seismic response of wharves, limitations in the modeling of wharf structures and the surrounding soil media have constrained the understanding of various features of the wharf response. This research provides new insights into the seismic behavior of wharves by using new and advanced structure and soil modeling procedures to carry out two and three-dimensional seismic analyses of a pile-supported marginal wharf structure in liquefiable soils. Furthermore, this research investigates the interaction between cranes and wharves and closely assesses the role of wharf-crane interaction on the response of each of these systems. For this purpose, the specific effect of wharf-crane interaction is studied by incorporating advanced models of the crane with sliding/uplift base conditions. To reduce the computational time required for three-dimensional nonlinear dynamic analysis of the wharf in order to be applicable for probabilistic seismic demand analysis, a simplified wharf model and an analysis technique are introduced and verified. In the next step probabilistic seismic demand models (PSDMs) are generated by imposing the wharf models to a suit of ground deformations of the soil embankment and pore water pressure generated for this study through free-field analysis. Convolving PSDMs and the limit states, a set of fragility curves are developed for critical wharf components whose damage induces a disruption in the normal operation of ports. The developed fragility curves provide decision makers with essential tools for maximizing investment in wharf retrofit and fill a major gap in seismic risk assessment of seaports which can be used to assess the regional impact of the damage to wharves during a natural hazard event.
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Fernandez, Carlos Javier. "Pile-structure interaction in GTSTRUDL." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/21418.
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Vasilescu, Andreea-Roxana. "Design and execution of energy piles : Validation by in-situ and laboratory experiments." Thesis, Ecole centrale de Nantes, 2019. http://www.theses.fr/2019ECDN0015/document.
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Les pieux énergétiques représentent une solution alternative intéressante, face à l’accroissement des besoins mondiaux en énergie et à la réduction de l’utilisation des énergies fossiles. L’objectif principal de la thèse est d’identifier et de quantifier les principaux facteurs influençant le dimensionnement des pieux géothermiques, qui sont impactés par les changements de température des pieux lors de leur activité. Pour ce faire, ce travail de thèse a été dressé en 3 campagnes expérimentales, dont deux à échelle réelle : (i) une première campagne à chargement thermomécanique contrôlé (Marne La Vallée), (ii) une seconde campagne en conditions d’utilisation réelles sous une station d’épuration (Sept Sorts) et (iii) une troisième campagne à l’échelle du laboratoire grâce à une nouvelle machine de cisaillement direct d’interface permettant l’étude du comportement thermo mécanique des interfaces sol-structure. Ces trois campagnes expérimentales ont pour but de quantifier l’effet de la température et des cycles de température sur le comportement des pieux énergétiques. Les premiers résultats expérimentaux de la campagne de Sept Sorts ont ensuite été simules dans le code LAGAMINE via la méthode des éléments finis, afin d’adopter une approche complémentaire permettant de mieux appréhender la réponse thermomécanique de ce type de pieu lors de l’activation géothermique. et (iii) une troisième campagne à l’échelle du laboratoire grâce à une nouvelle machine de cisaillement direct d’interface permettant l’étude du comportement thermo mécanique des interfaces sol-structure. Ces trois campagnes expérimentales ont pour but de quantifier l’effet de la température et des cycles de température sur le comportement des pieux énergétiques. Les premiers résultats expérimentaux de la campagne de Sept Sorts ont ensuite été simules dans le code LAGAMINE via la méthode des éléments finis, afin d’adopter une approche complémentaire permettant de mieux appréhender la réponse thermomécanique de ce type de pieu lors de l’activation géothermiqueEnergy piles, also called thermo-active piles, are an alternative solution to the increase in the global energy demand as well as in mitigating socio-economical stakes concerning the increase of energy costs due to fossil fuels. Energy piles are double purpose structures that allow transferring the loads from the superstructure to the soil and that integrate pipe circuits allowing heat exchange between the pile and the surrounding ground. The objective of this thesis is to identify and quantify the principal parameters involved in the geotechnical design of pile foundations impacted by temperature changes associated with geothermal activation. For this purpose, this research work was organized in 3 experimental campaigns: (i) A full scale load controlled test at Ecole des Ponts Paris-Tech, (ii) Full scale energy piles monitoring under real exploitation conditions at Sept Sorts, (Seine et Marne, France), (iii) Laboratory tests in order to assess the effect of temperature and temperature cycles at the soil-pile interface. The experimental results are used to estimate the effect of geothermal activation of a pile foundation, on its bearing capacity as well as on its long-term exploitation. Finally, preliminary numerical simulations were performed using a thermo-hydro mechanical model, using the finite element method code LAGAMINE able to capture the main phenomena
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Ferro, Newton Carlos Pereira. "Uma combinação MEC/MEF para análise de interação solo-estrutura." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-08122017-102331/.
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No presente trabalho, uma combinação do método dos elementos de contorno (MEC) com o método dos elementos finitos (MEF) é apresentada para a análise da interação entre estacas e o solo, considerado como um meio infinito tridimensional e homogêneo. O meio contínuo tridimensional de domínio infinito é modelado pelo MEC, enquanto as estacas consideradas como elementos reticulares são tratadas pelo MEF. As equações das estacas oriundas do método dos elementos finitos são combinadas com as do meio contínuo obtidas a partir do método dos elementos de contorno, resultando em um sistema completo de equações, que convenientemente tratadas, proporcionam a formulação de coeficientes de rigidez do conjunto solo-estacas. Finalmente, uma formulação para a análise do comportamento não-linear do solo na interface com a estaca é desenvolvida, tornando o modelo mais abrangente.In the present work a combination of the Boundary Element Method (BEM) and the Finite Element Method (FEM) is used for pile-soil interaction analyses, considering the soil as a homogeneous, three-dimensional and infinite medium. The three-dimensional infinite continuous medium is modeled by the BEM, and the piles are, considered as beam elements, modeled by the FEM. This combination also is used for studying the interaction of plates sitting on a continuous medium. The pile equations generated from the FEM are combined with the medium equations generated from the BEM, resulting a complete equation system. Manipulating properly this equation system, a set of stiffness coefficients for the system soil-pile is obtained. Finally, to make the model more comprehensive, it presented a formulation to take into account the soil nonlinear behavior at the pile interface.
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Silva, Illanes Matias Felipe. "Experimental study of ageing and axial cyclic loading effect on shaft friction along driven piles in sands." Thesis, Grenoble, 2014. http://www.theses.fr/2014GRENI077/document.
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La capacité opérationnelle axiale en service de pieux battus reste une zone d'incertitude, en particulier pour les structures offshore. La recherche sur le terrain a montré que le frottement latéral peut augmenter au cours des mois ou des années après le battage. Si des tendances similaires se retrouvent dans des ouvrages offshore, les avantages en terme d'ingénierie de réalisation peuvent être très importants. D'autre part, les fondations sur pieux de plates-formes de gaz, de pétrole sont soumises à des chargements cycliques à long terme qui peuvent influencer leur capacité à l'arrachement. Les pieux battus en eau profonde connaissent un grand nombre de cycles complets de charge-décharge pouvant contribuer à la dégradation du frottement latéral lors de l'installation. Cette thèse vise à mieux comprendre les principaux résultats obtenus avec des pieux réels en sable siliceux, par le biais d'une recherche à échelle de laboratoire sous conditions environnementales contrôlées. Ce travail fait partie d'un programme de recherche commun entre le Laboratoire 3SR de Grenoble, l'Imperial College London, et le projet français de recherche ANR- SOLCYP. La réponse de l'interface sol-pieu lors de l'installation ainsi que les périodes de vieillissement et de chargements cycliques axiaux ont été étudiés au laboratoire en utilisant des pieux-modèles installés dans la chambre d'étalonnage de Grenoble. Plusieurs essais avec le pieu modèle Mini-ICP (instrumenté avec des capteurs de tension totale à la surface du pieu (SST) pour les mesures de contraintes radiales de cisaillement à 3 sections) ont permis l'analyse de chemin de contrainte locale à l'interface du pieu. Des capteurs miniatures ont en outre été installés dans le massif de sable pour une mesure de contrainte lors de l'installation du pieu et son chargement ultérieur. Les effets des méthodes d'installation, de la taille des particules de sable, ou de la saturation du sable et du chargement de l'environnement, ont été pris en compte pour le vieillissement de la capacité. Les évolutions locales de l'interface radiale et du cisaillement sont en accord avec les prédictions des méthodes de conception modernes basées sur le CPT. Des preuves d'effets d'échelle soulignent l'importance des conditions aux limites appliquées à la modélisation physique. Des séries d'essais non-alternés purement en traction, ainsi que des essais alternés ont été réalisés sous contrôle en charge ou en déplacement. Les mesures locales effectuées dans les chemins de contraintes effectives montrent une contraction radiale de la masse de sable au voisinage du pieu. Les incréments de l'amplitude de charge et du déplacement imposé accélèrent les taux de dégradation cyclique. Un nouveau diagramme de stabilité cyclique a été réalisé, en résumant les essais de chargement cycliques axiaux pour les pieux foncés et battus dans du sable siliceux moyennement dense. Des mécanismes complexes comme la rupture des grains et des changements de densité locale à l'interface du pieu peuvent affecter la réponse des pieux. La cinématique derrière leur installation et l'interaction avec le sol environnant reste encore très limitée. Comprendre comment un matériau granulaire interagit avec le pieu est important pour étudier la réponse globale du pieu. Les observations globales du comportement des pieux dans la chambre d'étalonnage ont été modélisées à une échelle micro en utilisant la tomographie aux rayons X du Laboratoire 3SR à Grenoble. Le programme expérimental comprenait des essais sur une chambre d'étalonnage modèle afin d'analyser le champ de déplacement lors de l'installation d'un pieu modèle, à l'aide des techniques de corrélation d'images (DIC) en trois dimensions. Des analyses micromécaniques d'échantillons «intacts» récupérés post mortem à l'interface du pieu ont été également effectuées pour mettre en évidence de possibles changements radiaux de densité ainsi que la rupture des grainsThe operational in-service axial capacity of driven piles remains an area of uncertainty, especially for offshore structures. Field research has demonstrated that axial shaft capacities may increase over the months or years after driving. If similar trends apply offshore, the realisable engineering benefits are very significant. On the other hand, the piled foundations of oil/gas platforms and wind/water turbines are subject to long term environmental and in service cyclic loading due for example to waves, vibrations and storms that may also affect their shaft capacity. Deep driven piles experience large numbers of full load-unload cycles that contribute to shaft capacity degradation during installation. This thesis aims to improve understanding of the main results obtained with full-scale piles in silica sand through a laboratory scale investigation performed under controlled environmental conditions. This work was part of a joint research programme between the Grenoble Laboratory 3SR and Imperial College London, and the French National SOLCYP research project. The response of the soil-pile interface during installation, ageing periods and cyclic loading tests have been studied using laboratory model piles installed in the large Grenoble Calibration Chamber. Several tests with the Mini-ICP pile allow the analyses of local stress path at the pile's interface. This model pile is instrumented with surface stress transducers (SST) for local measurements of total and radial shear stresses at 3 different sections along the pile's shaft. In addition, miniature soil stress transducers were installed into the sand mass for total stress measurements during pile installation and loading. Possible ageing effects as installation methods, sand particle size, sand saturation and environmental loading were studied. Local evolution of interface radial and shear stresses agree with predictions from modern CPT based design methods. Evidence of possible scale effects remark the importance of the boundary conditions applied in physical modelling. Series of one-way purely tensile and two-way axial cyclic loading tests were performed under load and displacement control. Local measurements made of the effective stress paths shows radial contraction of the sand mass in the vicinity of the pile. Increments in loading amplitude and imposed displacements accelerate cyclic degradation rates. A new interactive shaft stability chart was produced as a summary of axial cyclic loading tests for both jacked and driven piles in medium dense silica sand. Laboratory tests confirm findings from field tests where one-way low amplitude cycles lead to beneficial increases in tensile pile capacity of up to 20%. Complex mechanisms as grain breakage and local density changes at the pile's interface. The kinematics behind the installation of piles and its interaction with the surrounding soil is still limited. Understanding how granular material interacts with the pile may reveal important to understand the global pile response. The global observations of the pile behaviour from calibration chamber tests were modelled at a micro scale using Micro Computed Tomography at the Grenoble Laboratory 3SR. The experimental campaign included tests on a model calibration chamber devoted to the displacement field analyses during the installation of a model piles using three dimensional (3D) digital image correlation (DIC). Micromechanical analysis of « intact » post-mortem samples recovered at the pille's interface were also conducted for evidences of radial density gradient and grain breakage
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Mokeddem, Abdelhammid. "Modélisation géomécanique et probabiliste des rideaux de palplanches : prise en compte de l’interaction sol-structure et de la variabilité spatiale du sol." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0057/document.
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Le comportement géomécanique des ouvrages géotechniques à l’exemple des rideaux de palplanches est entaché d’incertitudes épistémiques liées aux hypothèses régissant le modèle géomécanique de calcul, mais aussi d’incertitudes aléatoires liées à la variabilité spatiale du sol. L’objectif principal de cette thèse est de mieux appréhender l’effet de ces incertitudes sur le comportement d’un rideau de palplanches. Pour cela le présent mémoire s’articule autour de quatre points principaux : Le premier point est relatif d’une part à l’analyse des hypothèses utilisées pour la modélisation géomécanique d’un rideau de palplanches et d’autre part à l’extension de la méthode des coefficients de réaction d’un système unidimensionnel basé sur une poutre et des appuis élastoplastiques à un système bidimensionnel de plaque orthotrope sur le même type d’appuis (MISS-CR-PLQ). Le deuxième point concerne la modélisation de la variabilité spatiale du sol. Après une comparaison entre deux méthodes de génération de champs aléatoires nous avons retenu la méthode Circulant Embedding pour son efficience. Plusieurs études paramétriques ont été menées pour analyser les effets des hypothèses prises lors de la génération des champs aléatoires. Le troisième point concerne la mise en place d’une démarche mécano-fiabiliste permettant d’intégrer la variabilité spatiale du sol pour le cas des rideaux de palplanches. Le quatrième point est consacré à l’application de la démarche développée pour un cas d’étude à travers des analyses probabilistes et fiabilistes. L’influence des paramètres statistiques (e.g. les longueurs de corrélations, la corrélation croisée, …), mécanique et géométrique a été étudiéeThe geomechanical behaviour of geotechnical structures such as sheet pile walls is subjected to epistemic uncertainties due to geomechanical models’ assumptions and also the aleatory uncertainties which could be related to the soil spatial variability. The main objective of this thesis is to gain more insight into the effect of these uncertainties on the sheet pile behaviour. To this end, this thesis focuses on four main issues: The first one is related on the one hand to the analysis of the used geomechanical hypotheses for modelling of retaining walls. On the other hand, to extend the one-dimensional subgrade reaction method which is based on a beam relying on elastoplastic supports to a two-dimensional system that call to an orthotropic plate relying on the same supports (MISS-CR-PLQ). The second issue concerns the soil spatial variability modelling. After a key comparison between two random field generation methods, we selected the Circulating Embedding method for its efficiency. Several parametric studies have been conducted to analyse the effects of different assumptions of random field generation. The third issue is related to the implementation of the proposed mechanical-reliability approach taking into account the soil spatial variability. The last issue is devoted to the application of the developed approach to a case study through probabilistic and reliability analyses. The influence of statistical parameters (e.g. correlation lengths, cross-correlation,...), mechanical and geometrical has been examined
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Balachowski, Lech. "Différents aspects de la modélisation physique du comportement des pieux : chambre d'étalonnage et centrifugeuse." Grenoble INPG, 1995. http://www.theses.fr/1995INPG0067.
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Ce travail de recherche a ete effectue au sein du groupe geomecanique et ouvrages du laboratoire sols, solides, structures. Il concerne l'etude du comportement des pieux de grande dimension utilises comme fondations de structures en mer dans des sables denses. Cette etude a ete menee a l'aide de deux grands outils de modelisation physique: la chambre d'etalonnage du laboratoire 3s et la centrifugeuse du l. C. P. C de nantes. Les pieux installes pour des plates-formes petrolieres sont en general des pieux battus a base ouverte. Les essais de pieux realises en chambre d'etalonnage du laboratoire 3s ont permis d'etudier le comportement du bouchon a l'interieur du tube pendant le battage et le chargement statique. Ils ont montre l'influence de la profondeur simulee, de la densite du massif de sable et de sa surconsolidation sur la mobilisation de la resistance de pointe et du frottement lateral. Une allure plutot parabolique de l'evolution de la resistance de pointe et du frottement lateral avec la surcharge verticale appliquee au massif a ete observee. Les essais penetrometriques realises dans les memes conditions de densite et de confinement ont permis de proposer les regles penetrometriques pour le dimensionnement des pieux en mer. L'extrapolation des resultats de frottement mesure sur le modele au prototype reel peut poser des problemes lies a des effets d'echelle. Les essais d'arrachement de pieux-modeles en centrifugeuse du l. C. P. C de nantes ont permis d'evaluer l'effet d'echelle en frottement lie au rapport taille du modele/ taille des grains. Cet effet d'echelle est exprime en fonction du niveau de contraintes et du rapport taille du modele/ taille des grains. Il est compare a celui qu'on peut determiner a partir d'essais de cisaillement d'interface sol-structure. L'ensemble des experiences menees permet d'une part de deboucher sur des methodes de dimensionnement moins conservatives que celles habituellement utilisees en offshore, d'autre part de confirmer l'importance de la prise en compte du comportement d'interface sol-structure dans la modelisation numerique
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Wilson, Daniel W. "Soil-pile-superstructure interaction in liquefying sand and soft clay /." Davis, Calif. : Center for Geotechnical Modeling, Dept. of Civil and Environmental Engineering, University of California, Davis, 1998. http://cgm.engr.ucdavis.edu/download/html.
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Garnica-Anguas, Paul. "Simulation numérique du frottement entre solides par équations intégrales aux frontières et modèle d'interface non linéaire : application aux pieux." Grenoble 1, 1993. http://www.theses.fr/1993GRE10143.
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L'interaction sol-structure est traitee comme un probleme de contact entre deux solides elastiques. Cela suppose que les non-linearites soient localisees a l'interface. Sur un plan numerique, nous abordons sous un angle continu le probleme de frottement entre solides, a l'aide de la methode des equations integrales aux frontieres. La premiere partie est dediee a la mise en equations du probleme de contact avec frottement. La deuxieme partie est consacree au perfectionnement d'un modele d'interface sol-structure de type vectoriel et a dependance directionnelle. Ce modele est base sur le principe d'une interpolation dite rheologique et privilegie la notion de chemin de cisaillement d'interface. La dilatance et la contractance localisees jouent un role fondamental dans le comportement d'interface. La troisieme partie traite des applications a la simulation numerique d'essais d'arrachement de pieux en chambre d'etalonnage ou en centrifugeuse, et ceci en trois dimensions. Une serie de resultats est presentee et commentee
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Li, Peng Loehr J. Erik. "Numerical analysis of pile group within moving soils." Diss., Columbia, Mo. : University of Missouri--Columbia, 2008. http://hdl.handle.net/10355/6691.
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Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 25, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dissertation advisor: Dr. Erik Loehr. Vita. Includes bibliographical references.
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Abdelhedi, Anouar. "Modélisation de l'effet de groupe dans le clouage des pentes." Paris 6, 1986. http://www.theses.fr/1986PA066042.
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De récentes expérimentations réalisées sur des sites réels, ont permis de mettre en évidence la complexité du comportement de groupe de pieux dans une pente instable. On fait le point sur les méthodes existantes et on approfondit l'étude du mécanisme du comportement du sol au voisinage d'une rangée de pieux en se limitant au phénomène d'interaction sol-pieu. Apres étude bibliographique du phénomène donnant lieu à la programmation de deux des méthodes les plus significatives, on réalise deux approches en déformation: modélisation en continuum élastique permettant de prendre en compte une géométrie de maillage des pieux quelconques et d'appliquer au groupe une sollicitation en déplacement très générale, modélisation s'appuyant sur la méthode des éléments finis et sur un modèle bidimensionnel horizontal simulant l'écoulement du sol entre une rangée de pieux. Comparaison de diverses méthodes.
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Chin, Victor B. L. "The dynamic response of pile-soil interfaces during pile driving and dynamic testing events." Monash University, Dept. of Civil Engineering, 2003. http://arrow.monash.edu.au/hdl/1959.1/9421.
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Haskell, Jennifer Jane Margaret. "Guidance for the design of pile groups in laterally spreading soil." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648830.
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Antoine, Pierre-Cornélius. "Etude des dalles sur sols renforcés au moyen d'inclusions rigides ou non." Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209997.
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Soft soil reinforcement by inclusion is a growing technique caracterized by a pile grid and a granular embankment introduced between the reinforced soil and the structure. Unlike traditionnal methods, the load is partially transferred to the pile heads by arching in the embankment. The application area of this research focuses on the shallow foundations case, in which the thickness of the embankment is small. The litterature review shows that only a few studies were dedicated to that case, and that fundamental questions remains concerning the load transfer in the embankment. Chosen method for this research consists in two-dimensionnal physical modelling, analysis of the conducted simulations, and development of an analytical model in order to predict the load transfer to the piles by arching in the embankment. The results of this PhD thesis provide original elements of evidence of the load transfer in the studied system, proposes an analytical model based on block division of the granular embankment by shear bands - which is in good agreement with experimental data - and lead to a better understanding of arching in soils.Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
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Luamba, Endi Samba. "Análise da interação casca plana-estaca-solo via acoplamento MEC/MEF tridimensional e suas aplicações." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-05062018-095120/.
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Analisam-se problemas de interação solo-estrutura através de uma formulação tridimensional obtida da combinação entre o Método dos Elementos de Contorno (MEC) e o Método dos Elementos Finitos (MEF). Os elementos estruturais que interagem com o solo são modelados pelo Método dos Elementos Finitos. E o solo, considerado como um meio semi-infinito, homogêneo, elástico linear e isotrópico, é modelado pelo Método dos Elementos de Contorno, empregando a solução fundamental de Mindlin. A solução fundamental de Mindlin é particularmente adequada para o tipo de problemas em análise, ou seja, problemas envolvendo sólidos tridimensionais semi-infinitos, já que é necessário discretizar apenas a superfície carregada do solo e/ou a linha de carga, e não todo o sólido tridimensional. A discretização da estaca em vários elementos finitos de viga tridimensional, permitindo a consideração de estacas de qualquer tamanho e submetidas a qualquer tipo de carregamento é uma das principais contribuições do trabalho. Outra contribuição diz respeito à consideração da ação horizontal no sistema placa-estaca-solo, diretamente aplicada na placa, e não redistribuída no topo das estacas. Por isso, os elementos estruturais laminares (radiers, sapatas e blocos de fundação) são modelados por elementos finitos de casca plana, possibilitando a consideração dos efeitos de flexão e de membrana. Essa abordagem permite a análise tanto de um grupo de estacas com bloco de capeamento rígido quanto de um radier estaqueado de qualquer rigidez. O acoplamento entre o MEC e o MEF é feito através de uma formulação mista em que a matriz dos coeficientes de influência do solo obtida pelo MEC é adicionada à matriz de rigidez dos elementos estruturais obtida pelo MEF, resultando em uma matriz de rigidez equivalente. Exemplos numéricos de interação estaca-solo, placa-solo e casca plana-estaca-solo são resolvidos para verificar, validar e demonstrar a eficiência das formulações desenvolvidas e implementadas.Soil-structure interaction problems are analyzed by a tridimensional formulation obtained combining the Boundary Element Method (BEM) and the Finite Element Method (FEM). Structural elements that interact with the soil are modeled by the Finite Element Method. And the soil, considered as a semi-infinite, homogeneous, linear elastic and isotropic medium, is modeled by the Boundary Element Method, using Mindlin\'s fundamental solution. Mindlin\'s fundamental solution is particularly suitable for the type of problems under analysis, viz. problems involving semi-infinite three-dimensional solids, since it is necessary to discretize only the loaded surface of the soil and/or the line-load, and not all the three-dimensional solid. The discretization of the pile in several three-dimensional beam finite elements, allowing the consideration of piles of any size and subjected to any type of loading, is one of the main contributions of this work. Another contribution is about the consideration of the horizontal load in the plate-pile-soil system, directly applied to the plate, and not redistributed on the top of the piles. Therefore, the laminar structural elements (rafts, footings, and foundation blocks) are modeled by flat shell finite elements, making possible the consideration of the effects of flexion and membrane. This approach allows the analysis of both a capped pile group and a piled raft of any stiffness. The coupling between the BEM and the FEM is performed through a mixed formulation in which the matrix of the soil\'s influence coefficients obtained by the BEM is added to the stiffness matrix of the structural elements obtained by the FEM, resulting in an equivalent stiffness matrix. Numerical examples of pile-soil, plate-soil and flat shell-pile-soil interaction are solved to verify, validate and demonstrate the efficiency of the developed and implemented formulations.
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Mosher, Reed L. "Three-dimensional finite element analysis of sheet-pile cellular cofferdams." Diss., Virginia Tech, 1991. http://hdl.handle.net/10919/37876.
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The conventional design methods for sheet-pile cellular cofferdams were developed in the 1940's and 1950's based on field and limited experimental observations. The analytical techniques of the day were unable to account for the complexities involved. The procedures used only rudimentary concepts of soil-structure interaction which do not exhibit the true response of the cofferdam for most circumstances. During the past decade it has been demonstrated that with proper consideration of the soil-structure interaction effects, the two-dimensional finite element models can be powerful tools in the investigation of cellular cofferdam behavior. However, universal implementation of the findings of these analyses was difficult to justify, since uncertainties remain about the assumptions made in arriving at the two-dimensional models. The only way to address these uncertainties was to perform a three-dimensional analysis.
This investigation has focused on the study of the three-dimensional behavior of Lock and Dam No. 26 (R) sheet—pile cellular cofferdam. The work involved the development of a new three-dimensional soil-structure interaction finite element code for cellular cofferdam modeling, and the application of the new code to the study of the behavior of the first- and second-stage cofferdam at Lock and Dam No. 26 (R).
The new code was used to study the cell filling process where the main cell is filled first with the subsequent filling of the arc cell. The finite element results show that interlock forces in the common wall were 29 to 35 percent higher than those in the main cell which are less than those calculated by conventional methods and compare well with the observed values.
After cell filling, the new code was used to model the cofferdam under differential loading due to initial dewatering of the interior of the cofferdam and changes in river levels. The finite element analysis results show that increasing differential water loads cause the confining stresses in the cell fill to increase which results in a decrease in the level of mobilized shear strength in the cell fill. This explains why the cellular cofferdam can withstand extremely high lateral loads and lateral deformations without collapsing.Ph. D.
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Costa, d'Aguiar Sofia. "Numerical modelling of soil-pile axial load transfer mechanisms in granular soils." Châtenay-Malabry, Ecole centrale de Paris, 2008. http://www.theses.fr/2008ECAP1075.
Full textAbstract:
L’objectif du travail présenté dans cette thèse est l'analyse et modélisation numérique des mécanismes de transfert de charge axiale entre sol-pieu, dans les sols granulaires. En utilisant un modèle élastoplastique tridimensionnel d'élément finis, une attention particulière est prêtée à la modélisation du comportement de l’interface sol-structure. Ainsi, les outils numériques nécessaires ont été mis en place et les outils existants ont été améliorés afin que, l'analyse de l'interaction sol-pieu soit faisable. Deux nouveaux modèles de comportement 3D sont implémentés dans le code d'éléments finis GEFDYN: un modèle d'interface et, pour le sol, une formulation axisymétrique du modèle multimécanismes de l’ECP, déjà existant et également connus sous le nom de Hujeux. La performance des deux modèles de comportement est comparée avec des résultats expérimentaux: d'abord, en utilisant des essais directs de cisaillement sol-structure et ensuite des essais de charge statiques de pieux en modèle physiques de centrifugeuse. La formulation théorique et l'exécution numérique des modèles constitutifs se sont donc avérées adéquats pour l'analyse des mécanismes de transfert de charge de sol-pieux, pour différents états initiaux du sol, différentes rugosités de la surface sol-pieux et différentes géométries. Finalement, l'applicabilité des modèles proposés est également étudiée pour un cas d’étude réel d’essais de charge statique de pieux forés et à tarière continus, menés dans le site expérimental ISC2 à l’occasion de la 2nd International Conference on the Site Characterization. L’identification des paramètres du sol et la simulation des essais de charge in-situ a été réalisé avec succésThe purpose of the work presented in this thesis, which has a theoretical and numerical character, is the analysis and numerical modelling of soil-pile load transfer mechanisms, in granular soils, when the pile is subjected to axial vertical loads. In the three dimensional elastoplastic finite element model used, particular attention is paid to modelling soil-structure interface behavior. The necessary numerical tools were implemented and the existing ones enhanced so that, the analysis of the soil-pile interaction problem is feasible. Two newly implemented 3D constitutive laws, in the GEFDYN finite element code, are proposed: an interface model and, for soil, an axisymmetric formulation of the existing ECP multimechanism model, also known as Hujeux model. The performance of both constitutive models is compared with experimental results. First, using soil-structure direct shear tests and then, using results of static pile load tests of centrifuge physical models. The theoretical formulation and numerical implementation of the constitutive models proved to be adequate for the analysis of the soil-pile load transfer mechanisms for different soil initial states, soil-pile surface roughness conditions, and different geometries. Finally, the applicability of the proposed models, is also studied for a real case study of pile static load tests carried out in the ISC'2 experimental site, at the occasion of the 2nd International Conference on the Site Characterization. Soil’s laboratory characterization tests and in-situ pile static load tests on bored and CFA piles are simulated, and results successfully compared
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Bel, Justin. "Modélisation physique de l’impact du creusement d’un tunnel par tunnelier à front pressurisé sur des fondations profondes." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSET002/document.
Full textAbstract:
Le travail de thèse présenté dans ce mémoire vise à analyser et à comprendre les mécanismes mis en jeu au niveau de l’impact du creusement d’un tunnel par bouclier à front pressurisé sur des fondations profondes avoisinantes. Cette thèse a été réalisée dans le cadre du projet européen NeTTUN, au sein du Laboratoire de Tribologie et de Dynamique des Systèmes (LTDS) de l’ENTPE. L’approche phénoménologique conduite lors de ces travaux repose sur deux importantes campagnes expérimentales réalisées à l’aide d’un dispositif unique au plan international de modèle réduit 1g de tunnelier à pression de terre (échelle de l’ordre de 1/10eme). La forte originalité de ce dispositif est de pouvoir simuler de façon réaliste les principales étapes du processus tridimensionnel d’excavation mécanisé d’un tunnel. Dans le cadre de cette thèse, le dispositif existant de modèle réduit de tunnelier a dans un premier temps été reconfiguré afin de pouvoir répondre aux besoins du programme expérimental envisagé. Des modèles physiques de fondations profondes (pieux et groupes de pieux) et de barrières de protection ont été conçus dans le cadre des lois de similitude, fabriqués et instrumentés. Deux campagnes expérimentales d’envergure ont été réalisées en massif de sable sec : l’une concerne les effets du passage d’un tunnelier à front pressurisé sur des fondations profondes avoisinantes (pieux, groupe de pieux), l’autre traite de l’efficacité de barrières de protection (parois moulées) utilisées pour limiter ces effets. Différents paramètres qui influencent l’interaction tunnelier - sol - fondations ont été considérés comme la distance relative tunnel / fondation, la pression frontale de soutènement appliquée par le TBM sur le terrain ou encore la hauteur des barrières de protection. L’analyse phénoménologique menée à l’échelle du modèle concerne en particulier l’évolution des champs de contraintes et de déplacements dans le terrain autour du tunnelier, les déplacements relatifs sol - pieu et sol- barrière, la redistribution des efforts au sein des fondations. L’importante base de données et d’analyse ainsi constituée a été mise à profit pour la validation d’outils de modélisation numérique développés par l’Université de Rome au sein du projet NeTTUNThe major goal presented in this thesis was to analyze and investigate the mechanisms, which are involved in the impact of the tunnels excavated thanks to an Earth Pressure Balanced Shield on nearby deep foundations. This thesis was realized in European project NeTTUN and the work had been done in the Laboratory of Tribology and Systems Dynamics (LTDS) of ENTPE. During these works, phenomenological approach was based on two important experimental campaigns carried out using a unique device at the international level of a 1g scale model of earth-pressure tunnel boring machine (scale of the order of 1 / 10). The state of the art of this device was to be able to simulate in possibly realistic way the main stages of the three-dimensional process of mechanized excavation of a tunnel. In the framework of this thesis, the existing model tunneling machine device was initially reconfigured in order to reach the expectations of the experimental program envisaged. Physical models of deep foundations (piles and groups of piles) and protective barriers were designed under the similitude laws, manufactured and instrumented. The two large-scale experimental campaigns have been carried out in a dry sand massif. The first one concerned the effects of the passage of a pressurized tunnel boring machine on nearby deep foundations (piles, group of piles), whereas another one dealed with the effectiveness of mitigation procedure (diaphragm walls) used to limit these effects. Different parameters that influenced on the tunneling: soil - foundation interaction considered as the relative tunnel / foundation distance, the frontal face pressure applied by the TBM in the field or the height of the protective barriers. The phenomenological analysis carried out at the scale of the model concerned in particular the evolution of the fields of stresses and displacements in the ground around the tunnel boring machine, relatives pile / soil and wall / soil displacements and the redistribution of stresses along the pile foundations. The large database and analysis constituted was used for the validation of numerical modeling tools developed by the University of Rome within the NeTTUN project
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Wu, Guoxi. "Dynamic soil-structure interaction: pile foundations and retaining structures." Thesis, 1994. http://hdl.handle.net/2429/7158.
Full textAbstract:
This thesis deals with two important topics in soil-structure interaction: seismic earth
pressures against rigid walls and the seismic response of pile foundations. These two disparate problems are linked by a common method of solution which is an approximation
to the response of the half-space, either linear or non-linear.
The approximate formulation permits analytical solutions against rigid walls when
the backfill is uniform and elastic. The solution agrees very closely with an existing exact solution. For elastic non-homogeneous backfills and for non-linear soil response the
approximate formulation is expressed using the finite element method.
An efficient computer program SPAW has been developed to determine dynamic
thrusts and moments against rigid walls for arbitrary non-homogeneous soil layers. Results of analyses show that the peak dynamic thrusts are larger for a uniform soil profile
than when the shear modulus of the soil varies linearly or parabolically with depth. The
program SPAW also possesses the ability of modelling the effect of soil non-linearity on
dynamic thrusts. Studies showed that an increase of peak dynamic thrust may be expected due to soil non-linearity, compared with results from a linear elastic analysis.
A quasi-3D finite element method of analysis has been proposed to determine dynamic response of pile foundations subjected to horizontal loading. A computer program
PlLIMP has been developed for the analyses of elastic response of pile foundations including the determination of pile impedances as a function of frequency. The analysis
is conducted in the frequency domain. The program can analyze single piles and pile
groups in arbitrary non-homogeneous soil layers.
Another quasi-3D finite element computer program PILE3D has been developed for
the analysis of non-linear response of pile foundations in the time domain. The program
is suitable of dynamic analyses of single piles and pile groups. The soil non-linearity
during shaking is modelled using a modified equivalent linear method. Yielding of the
soil is taken into account and there is a no-tension option controlling the analysis.
The proposed quasi-3D model has been validated using the elastic solutions from
Kaynia and Kausel (1982), Novak and Nogami (1977) and Novak (1974), Fan et al.
(1991), data from full scale vibration tests of a single pile and a 6-pile group, and data
from centrifuge tests of a single pile and a 2x2 pile group under strong shaking from
simulated earthquake. Excellent results have been obtained using the proposed method.
Time-dependent variations of dynamic impedances of pile foundations during shaking
have been evaluated for the model pile foundations used in the centrifuge tests. The
analyses quantify the reduction in the stiffnesses of the pile foundations with the increased
level of shaking. The translational stiffness Ƙѵѵ decreases the most during strong shaking;
the rotational stiffness Ƙθθ decreases the least. However, the damping of pile foundations
increases with the level of shaking.
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Yeh, Chih-Kai, and 葉志凱. "Soil-Structure Interaction Simulation for Concrete Pile-Shafts Subjected to Lateral Loads." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/75120957255897892532.
Full textAbstract:
碩士國立中興大學
土木工程學系所
100
This study uses the numerical method to analyze inelastic beam on nonlinear Winkler''s foundation model, considering the soil-pile interaction effect. The nonlinear behavior of the pile is described by the moment curvature relationship of the section, and the lateral soil pressure is modeled as the resistance from a serious of nonlinear p-y springs. A set of nonlinear differential equations is developed to simulate the laterally loaded soil pile system. Using the mathematical software “Mathematica” and finite element analysis software “OpenSees” to establish the model into the behavior inductive analysis, the pile deformation, curvature distribution and lateral soil pressure along the pile are obtained by the numerical solution of models for various level of pile head displacement. Analysis results also clearly illustrate the formation of plastic hinge, development of plastic rotation, redistribution of bending moment after yielding, and the rapid increase of inelastic curvature at the plastic hinge.
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Kuan-MingWu and 吳冠民. "Nonlinear finite element analysis of bridge structure under the soil-pile interaction." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/tc979k.
Full text
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Lai, Shin-cheng, and 賴信成. "Effective stress analysis for dynamic behavior of super structure- pile foundation- soil interaction." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/61467848460661662043.
Full textAbstract:
碩士國立高雄第一科技大學
營建工程所
96
Pile foundations have been frequently used to support large infrastructure on the soft ground or ground with saturated sand. During earthquakes, the ground deforms, affecting the bearing capacity of the pile foundations. Over the past years, many damages of superstructures due to this effect have been reported. Thereafter, some researchers have also researched this issue using physical models with large shaking table tests and centrifugal tests and numerical analysis on simulating the seismic interaction of soil- pile- structures. Dynamic behavior is studied numerically using a three-dimensional effective stress analysis in this research. This numerical model includes cyclic elasto-plastic soil model, which is used to reproduce dynamic behaviors of sandy soils, and an axial force dependence model, which is employed to simulate the dynamic pile stiffness due to axial loading changes. Dynamic behavior of a 2×2 group piled foundation installed in a two layered ground and a five-story building that tilted northeastward because of serious pile damage during the 1995 Kobe earthquake due to major earthquake is studied numerically using a on three dimensional effective stress analysis to investigate the seismic behavior of group pile foundations. It is found that possible failure of the pile foundation would come from a large bending moment taking place on the pile head, which is inherited from the inertia loading of upper structure. Then the large deformation of ground occurs when sandy soils liquefy. Deformation starts to dominate damage level on the pile segment at boundary of soil layers in which one is liquefied and the other is not.
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Ghalibafian, Houman. "Evaluation of the effects of nonlinear soil-structure interaction on the inelastic seismic response of pile-supported bridge piers." Thesis, 2006. http://hdl.handle.net/2429/18276.
Full textAbstract:
This dissertation presents an evaluation of the effects of nonlinear soil-structure interaction (SSI) on the inelastic seismic response of pile-supported bridge piers on soft soil. The research was carried out by studying the dynamic responses of prototype soil-foundation-bridge pier systems subjected to earthquake ground motions. The responses were obtained by performing nonlinear dynamic analyses using a commercial finite difference program. The nonlinearities of the soil, the structure, and the soil-structure interface were all accounted for. The numerical analysis method was carefully validated by verifying the modeling of each component of the system and by verifying the modeling of the system as a whole through analyzing an instrumented bridge pier subjected to an actual earthquake. The dynamic responses of the prototype bridge piers were computed with and without consideration of SSI (i.e. flexible-base versus fixed-base piers), and with and without consideration of the inelastic behaviour of the piers. This work explores the efficient implementation and practical application of the direct methods of SSI analysis with a system approach. It presents the seismic demands of the prototype piers and foundations, and provides a quantified picture of the effects of SSI on the ductility and the total displacement demands of the piers as functions of their natural period. This study investigates the effects of the modeling assumption of the structural elements (i.e. elastic versus inelastic behaviour) on the estimated demands, and demonstrates that SSI analyses with elastic structures cannot always provide plausible predictions of the inelastic responses. The effects of SSI on the seismic demands of the bridge piers are also studied probabilistically in order to consider the uncertainties in the system parameters and to account for the dispersions introduced by the variability of input ground motions and soil conditions. Subsequently, SSI modification factors are proposed to estimate the demands of the flexible-base piers from their corresponding fixed-base demands. The proposed method is probabilistic and quantifies the uncertainties involved in computing the modification factors. Finally, this work demonstrates the shortcomings of the nonlinear static pushover analysis for seismic demand estimation of pile-supported bridge piers when SSI is significant.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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Lim, Seok Gyu. "Development of Design Guidelines for Soil Embedded Post Systems Using Wide-flange I-beam to Contain Truck Impact." Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9257.
Full textAbstract:
Anti ram perimeter barriers are part of the protection of important facilities such as power plants, air ports and embassies against unrestricted vehicle access. Many different systems can be used to achieve the containment goal. One of these systems makes use of soil embedded posts either single posts if the soil is hard enough or groups of soil embedded posts tied together by beams if the soil is not hard enough for a single post to stop the in-coming truck. The design of these soil embedded posts needs to take account a number of influencing factors which include the soil strength and stiffness, the post strength and stiffness, the mass of the vehicle and its approach velocity.
This dissertation describes the work done to develop a set of design recommendations to select the embedment of a single post or group of posts. The post is a steel beam with an H shape cross section: W14X109 for the single post system and W14X90 for the group system with a double beam made of square hollow steel section HSS8X8X1/2. The spacing of the posts for the group includes 2.44 m, 4.88 m, and 7.32 m. The soil strength varies from loose sand and soft clay to very dense sand and very hard clay. The vehicle has a mass of 6800 kg and the velocities include 80 km/h, 65 km/h, and 50 km/h.
The design guidelines presented here are based on 10 medium scale pendulum impact tests, 2 medium scale bogie impact tests, 1 full scale impact test on a single post, 1 full scale impact test on a group of 8 side by side posts with a 5.2 m spacing and connected with two beams, approximately 150 4-D numerical simulations of full scale impact tests using LS-DYNA, as well as fundamental theoretical concepts.
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Jones, Kimberly. "Numerical investigation of lateral behaviour of a large pile group supporting an LNG tank." Thesis, 2021. http://hdl.handle.net/1828/13334.
Full textAbstract:
Liquefied natural gas (LNG) storage tanks are often supported by very large pile groups (≥ 100 piles). As these superstructures tend to be located along coastal areas, there is often a high risk of extreme lateral loading caused by either seismic, flooding or hurricane activity. In many cases, the foundation design can be governed by the required lateral resistance. At present, the responses of large pile groups subjected to lateral loading are not well understood. Published guidance for design is premised upon experimental testing of smaller pile groups (< 25 piles), and no additional commentary is provided to advise the design for groups of a larger scale.
A typical approach for design of laterally loaded pile groups uses the beam on Winkler foundations method, where nonlinear p-y curves are reduced by a p-multiplier to account for the group effects. Alternatively, an average p-multiplier known as a group reduction factor (GRF) can be used. Chapter 1 details the study of using 3D continuum finite element (FE) models to measure the group effects in large pile groups using p-multipliers and GRF. Soil conditions, pile spacing, pile number, and pile head condition were varied to observe their effects. The study also looked at the effect of the circular configuration of pile groups used in LNG tank foundations. The design standards and prevailing methods were shown to overestimate trailing row p-multipliers for large pile groups, particularly with larger pile spacing. Based on the study data and published data, a predictive equation was proposed for estimating GRF of a laterally loaded large pile group.
In addition, geotechnical engineers tend to evaluate the lateral responses of pile groups regardless of the presence of superstructures. It is not known whether this approach is suited for large infrastructure such as LNG storage tanks and their respective foundations. Chapter 2 captures the results from 3D finite element (FE) models used to observe the integrated tank and piled foundation behaviour and evaluate whether the current design approach used in practice is suitable. In addition, changes to soil-foundation stiffness, including varying soil conditions and pile spacing, were made to observe their effects. The results found that the foundation responses in the integrated model varied significantly from models which only considered the foundation. It was also found that the amount of LNG in the tank, soil conditions, and pile spacing also affected the lateral pile responses, particularly the leading and trailing piles.Graduate
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McCullough, Nason J. "The seismic geotechnical modeling, performance, and analysis of pile-supported wharves." Thesis, 2003. http://hdl.handle.net/1957/30419.
Full textAbstract:
This dissertation presents the results of a research effort conducted to better
understand the seismic performance and analysis of pile-supported wharves. Given the
limited number of well-documented field case histories, the seismic performance of
pile-supported wharves has been poorly quantified, and the analysis methods
commonly employed in engineering practice have generally not been validated. Field
case histories documenting the seismic performance of pile-supported wharves
commonly contain only limited information, such as approximations of wharf and
embankment deformations and peak ground surface accelerations. In order to
supplement the field data, five centrifuge models were dynamically tested, with each
model containing close to 100 instruments monitoring pile bending moments, excess
pore pressures, displacements, and accelerations.
The combined field and model database was used to develop seismic
performance relationships between permanent lateral deformations, maximum and
residual bending moments and peak ground surface displacements. Key issues such as
the seismic performance of batter piles, the development of large moments at depth,
and the need to account for permanent lateral deformations for high levels of shaking,
even for very stable geometries, are discussed.
The field data and model studies were also used to validate two geotechnical
seismic performance analysis methods: 1) the limit-equilibrium based rigid, sliding
block (Newmark) method, and 2) an advanced finite-difference effective stress based
numerical model (FLAC). Favorable predictions were generally obtained for both
methods, yet there was a large variability in the results predicted using the rigid,
sliding block method. The numerical model predicted the permanent deformations,
pore pressure generation, and accelerations fairly well, however, pile bending
moments were poorly predicted. The results of this research clearly highlighted the
need for analysis validation studies, and note the uncertainty and variability inherent in
the seismic performance of complex structures. The lack of adequate validation may
lead to an over-confidence and false sense of security in the results of the seismic
analysis methods.
This dissertation specifically addresses pile-supported wharves, yet the results
presented herein are applicable to other pile-supported structures located near, or on,
slopes adjacent to the waterfront, such as: bridge abutments, railroad trestles, and pile-supported
buildings near open slopes. Performance and analysis issues common to all
of these structures are addressed, such as: liquefiable soils, lateral pile response in
horizontal and sloping soils, the lateral behavior of piles in rock fill, and global slope
stability, as well as the general observed seismic behavior.Graduation date: 2004