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Chaudhry, Anjum Rashid. "Static pile-soil-pile interaction in offshore pile groups". Thesis, University of Oxford, 1994. http://ora.ox.ac.uk/objects/uuid:7b4c8d56-184f-4c8d-98c9-2d9c69a1ef55.
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This thesis is a theoretical study, using both finite element and boundary element methods, of the behaviour of single-piles and pile groups under vertical and lateral loading. It offers an improved understanding of the soil-structure interaction that occurs in pile groups, particularly closely spaced piles subjected to lateral loads. The potential of a two- dimensional idealisation of what is a three-dimensional problem is demonstrated by achieving real insight into the complex nature of pile-soil and pile-soil-pile interaction in pile groups. A new load transfer mechanism is presented for a rigid, axially loaded vertical pile. From this an improvement is then derived to the analytical solution for pile head settlement given by Randolph and Wroth (1978). The improved mechanism has the further merit that it can be applied also to solutions for flexible piles and pile groups. The improved analytical solution is further adapted in the development of two correcting layers specifically for vertically loaded piles to model infinite boundaries in the finite element model. The correcting layers help in establishing superiority of the finite element method over the boundary element method. To model pile-soil interaction, a purely cohesive interface element is developed and then validated by performing various two-dimensional test problems, including stability analysis of flat surface footings. Footing-soil interface tension is successfully modelled in this way - an outcome that entails a significant modification to the Hansen (1970) bearing capacity solution. Stability analysis is also carried out of conical footings using a three-dimensional finite element model: the results help to explain the applicability of the existing bearing capacity theories to conical footings. The ultimate lateral soil reaction is determined and various pile loading stages are investigated through parametric studies. Study of the stage immediately following pile installation (i.e. the consolidation stage) highlights the need to develop an effective stress analysis for laterally loaded piles. Pile-soil interaction is studied using the cohesive interface element presented earlier, which proves to be quite successful in smoothing out the stress discontinuities around the pile. A new material model for frictional soils is presented, and validated by using it to model an extension test: it captures well post-peak behaviour and takes care of the effects of dilation on the response of laterally loaded piles. Finally, mechanisms of interaction in closely spaced pile groups are studied. Simple analytical expressions are derived which quantify the effects of interaction. A new method of analysis is presented for single-piles and pile groups which offers a considerable degree of reliability without having to do either impossibly expensive full scale field tests or prohibitively expensive full three-dimensional analysis using the currently available computers.
2
Dash, Suresh R. "Lateral pile soil interaction in liquefiable soils". Thesis, University of Oxford, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543468.
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Lee, Lin. "Soil-pile interaction of bored and cast in-situ piles". Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.633219.
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The research presented in this thesis was undertaken to investigate the changes of the engineering properties of clay surrounding bored piles induced by the ion migration and hence the variation of shaft carrying capacity with time. As lime forms one of the major chemical compositions in cement, it follows that the cement from the bored piles will have a similar effect of improving the engineering properties of the clay adjacent to the bored piles. A number of model piles were constructed in order to study the soil-pile chemical interaction. At a specific time, the piles were subjected to load tests and the clay surrounding the piles was tested for its engineering and chemical properties. The load-settlement curves show that failures take place at large displacements compared with the typical values of 0.5% to 2% of pile diameter normally used. From the tests and analysis of other researchers' works together with the results from this research, equations were drawn for determining the settlement to fully mobilize the shaft resistance of pile. The results obtained showed that the shaft resistance of the bored pile increased with time over the monitoring period investigated. Together with this, calcium and hydroxyl ions were detected in the clay surrounding the pile. It can be concluded that soil-pile chemical reaction does take place and it affects pile behaviour.
4
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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Mattar, Joe. "An investigation of tunnel-soil-pile interaction in cohesive soils /". Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=112577.
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Underground tunnels are considered to be a vital infrastructure component in most cities around the world. Careful planning is always necessary to ensure minimum impact on nearby surface and subsurface structures. This thesis describes the experimental and numerical investigations carried out at McGill University to examine the effect of existing pile foundation on the stresses developing in a newly constructed tunnel supported by a flexible lining system. A small scale testing facility was designed and built to simulate the process of tunnel excavation and lining installation in the close vicinity of pre-installed piles. Lining stresses were measured for different separation distances between the tunnel and the existing piles. Significant decrease in circumferential stresses was observed when the lining was installed at a distance that ranges between one to three times the tunnel diameter from the piles. Two-dimensional finite element analyses were also conducted to investigate the different aspects of the pile-soil-lining interaction including lining deformation, axial forces and bending moments. The measured lining stresses agreed with those obtained using finite element analysis. The results presented in this study provided an insight into understanding an important aspect of this soil-structure interaction problem.
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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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TOMBARI, ALESSANDRO. "Seismic response of extended pile shafts considering nonlinear soil-pile interaction". Doctoral thesis, Università Politecnica delle Marche, 2013. http://hdl.handle.net/11566/242686.
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Il sistema pila-palo è largamente diffuso nelle strutture da ponte grazie ai suoi vantaggi
economici e tecnici. Tuttavia questo sistema è fortemente influenzato dagli effetti
dell’interazione dinamica terreno-palo-struttura. In aggiunta all’allungamento del periodo
fondamentale della struttura, la cedevolezza della fondazione induce una componente
rotazionale del moto sismico sul sistema globale che non può essere considerata mediante
le comuni procedure di progettazione sismica. Sebbene siano stati sviluppati modelli
avanzati per considerare l’interazione terreno-palo-struttura sia in campo lineare e non
lineare, i modelli alla Winkler rappresentano uno degli approcci più versatili.
In questo lavoro, un modello nonlineare di trave su suolo alla Winkler è stata utilizzato per
indagare l’effetto sulla risposta della struttura dei principali aspetti legati al comportamento
nonlineare del sistema terreno-fondazione, come ad esempio la plasticizzazione del terreno
, la formazione di distacco all’interfaccia palo-terreno, il collasso delle pareti del foro e il
degrado o incrudimento ciclico del terreno in prossimità del palo.
Sono state eseguite analisi dinamiche incrementali per valutare gli effetti della durata del
moto sismico e le non linearità del terreno sulle prestazioni della pila-palo in vari profili di
terreno omogeneo e bistrato sia di argilla satura che di sabbia nello stato asciutto o saturo
considerando differenti livelli di compattazione.
Si è stabilita una procedura per eseguire le analisi dinamiche incrementali considerando gli
effetti sia sulla risposta sismica locale sia sulle prestazioni strutturali. Gli effetti
dell’interazione cinematica ed inerziale in campo non lineare sono stati analizzati mediante
un’ampia indagine parametrica. Le analisi hanno evidenziato il ruolo determinante della
componente rotazionale e della durata del moto sismico sulla risposta sismica della pilapalo.
I risultati ottenuti sono inoltre stati confrontati con quelli ottenuti mediante un
modello lineare. Infine, vengono fatte alcune considerazioni evidenziando le aree grigie
della comune pratica di progettazione.Single column bents on extended pile shafts are widely used in bridges for their economical and technical advantages. Nevertheless, this system is strongly affected by Dynamic Soil- Pile-Structure Interaction. In addition to the lengthening of the fundamental period of the structure, the compliance of the foundation induces a rocking component of the seismic motion experienced by the overall system that cannot be considered by following the procedures of a common seismic design practice. Although advanced models have been developed in order to account for Soil-Pile-Structure Interaction both in the linear and nonlinear range, Winkler-type models represent one of the most feasible approaches. In this work, a Beam on Nonlinear Winkler Foundation model is used to investigate the importance of features typical in soil nonlinear behaviour such as yielding, gapping, soil cave-in and cyclic hardening/degradation effects on the performance of extended pile shafts. A procedure to estimate the model parameters from geotechnical soil characterization is presented. Incremental Dynamic Analyses are performed to evaluate the effects of Ground Motion Duration and soil nonlinearity on the performance of extended pile shafts in various homogeneous and two-layered soil profiles, including saturated clay and sand in either fully dry or saturated state with different levels of compaction. A procedure to perform Incremental Dynamic Analysis, including effects on both site response analysis and on the structural performance, is established. Nonlinear kinematic and inertial interaction effects are analyzed by means of an exhaustive parametric investigation. The significant effects of the rocking component and the Ground Motion Duration on the seismic response of extended pile shafts are demonstrated. Comparisons with results obtained with a linear model are also presented. Finally, some considerations are drawn pointing out grey areas of the common design practice.
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Peiris, Thanuja Pubudini. "Soil-pile interaction of pile embedded in deep layered marine sediment under seismic excitation". Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/75518/1/Thanuja%20Pubudini_Peiris_Thesis.pdf.
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This research provides validated Finite Element techniques to analyse pile foundations under seismic loads. The results show that the capability of the technique to capture the important pile response which includes kinematic and inertial interaction effects, effects of soil stiffness and depth on pile deflection patterns and permanent deformations.
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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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GOMES, MARIA DO CARMO VORCARO. "PILE DRIVING AND ITS INFLUENCE ON SOIL". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 1997. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=1963@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOREste estudo objetiva reunir, em uma abordagem qualitativa, o que se conhece sobre as modificações, com o tempo, na capacidade de carga de estacas, fenômenos que, neste tr abalho,chamaremos recuperação e relaxação. A importância destas alterações é significativa: após a execução, as estacas podem manter a capacidade de carga inicial, -recuperar-, aumentando -a de uma porcentagem não previsível, mas que pode chegar a quadruplicá-la, ou -relaxar-, perdendo grande parte de sua resistência (até acima de 50 por cento). O peso econômico do desenvolvimento de tais fenômenos justifica por si a necessidade de melhor compreensão desses processos e, nessa dissertação, passo inicial de um projeto de pesquisa mais amplo na área, foram coletados e grupados resultados e observações sobre o tema. Foram escolhidos e transcritos casos representativos da literatura que contemplam a variedade de comportamentos do solo em função da cravação de estacas. Privilegiou-se as avaliações experimentais nas quais se constatou aumento ou redução da capacidade de carga em estacas cravadas com o decorrer do tempo, ou seja,recuperação e relaxação, respectivamente. Não houve preocupação de restringi -las às mais recentes, uma vez que, mesmo não dispondo do nível do desenvolvimento tecnológico atual, as intuições iniciais não estão muito distantes das propostas e modelos que lhes dão continuidade hoje. Conclui -se ser imprescindível à engenharia de fundações um conhecimento mais profundo que permita melhores e mais seguras previsões do desempenho, ao longo do tempo, de estacas cravadas, especialmente pelos riscos e prejuízos que sua ausência representa. Espera -se que a pequena parcela aqui apresentada, contribuindo para a ampliação da visão global do problema,estimule a adoção de práticas executivas cientificamente éticas. Para tal recomenda -se que, pelo menos, sejam trazidas a público as informações sobre a ocorrência desses fenômenos.
This work is intended to assemble, in the light of a qualitative approach, what is already known about the changes over time in the bearing capacity of piles, setup and relaxation. The importance of such alterations is significant. After the installation process, the piles may keep their initial loading capacity, set it up by increasing it from a non-predictable percentage (which may eventually quadruple) or relax, losing most of its resistance (up to over percent). The cost of such phenomena justifies per se the need of an improved comprehension of such processes, and in the present work, a first step of a broader research project, the results and observations on the subject were collected and assembled. Representative cases found in the literature which contemplate variety in soil behaviour due to the driving of piles were selected and transcribed. Experimental evaluations where a growth or reduction in the bearing capacity of driven piles over time, eg. set-up and relaxation, were given priority. It was not the concern of this work to restrict the set-up and relaxation processes to more recent research because the initial intuitions, though not in charge of the present technological development, were not so distant from the proposals and models which followed. We thus deem as essential to foundation engineering a further insight into the subject, which will permit better and safer anticipations of the behaviour of driven piles over time, in view of the risks and economic losses which may arise from its absence. It is hoped that the present dicussion, by contributing to further a qualitative global view of the matter, may give rise to the adoption of scientifically ethical practices. To such, it is recommended that the information on such phenomena be made public.
Este estudio tiene como objetivo reunir, com um enfoque cualitativo, lo que se conoce sobre las modificaciones en la capacidad de carga de estacas; fenómenos que, en este trabajo, llamaremos recuperación y relajación. La importancia de estas alteraciones es significativa: después de la ejecución, las estacas pueden mantener la capacidad de carga inicial, recuperar, aumentándola en un porcentaje no previsible, que puede llegar a quadruplicarla, o relajar , perdiendo grande parte de su resistencia (hasta más del por ciento). El peso económico del desarrollo de tales fenómenos justifica por sí mismo la necesidad de una mejor comprensión de estos procesos y esta disertación, paso inicial de un proyecto de investigación más amplio, se recolectaron y agruparon resultados y observaciones sobre el tema. Se escogieron y transcribieron los casos representativos de la literatura que contienen la variedad de comportamientos del suelo en función del clavado de estacas. Se privilegiaron las evaluaciones experimentales en las que se constató aumento o redución de la capacidad de carga en estacas clavadas, o sea, recuperación y relajación, respectivamente. No hubo preocupación de restringirlas a las más recientes ya que, incluso cuando no se dispone del nível del desarrollo tecnológico actual, las instituciones iniciales no están muy distantes de las propuestas y los modelos que le dan continuidad hoy. Se concluye que es imprescindible para la ingeniería de fundaciones un conocimiento más profundo que permita mejores y más seguras previsiones del desempeño, a ll largo del tiempo, de estacas clavadas, especialmente por los riesgos y perjuicios que su ausencia representa. Se espera que la pequeña parcela aqui presentada, contribuya a la ampliación de la visión global del problema, estimulando la adopción de prácticas ejecutivas cientificamente éticas. Para tal se recomienda que, por el momento, se hagan públicas las informaciones sobre la existencia de esos fenómenos.
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Guillement, Claire. "Pile – Soil Interaction during Vibratory Sheet Pile Driving : a Full Scale Field Study". Thesis, KTH, Jord- och bergmekanik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-136578.
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Urban construction sites require strict control of their environmental impact, which, for vibratory sheet pile driving, can include damage to nearby structures due to ground vibrations. However, the lack of knowledge concerning the generation of soil vibrations makes the prediction of ground vibration levels difficult. This MSc. thesis in particular, focuses on a crucial link in the vibration transfer chain: the sheet pile – soil interface, which is also one of the least documented. The aim of this thesis is first, to carry out a full-scale field test consisting in the monitoring of sheet pile and ground vibrations during sheet pile vibratory driving. And second, to analyze a selected portion of the collected data with focus on the sheet pile – soil vibration transfer. Both aspects of the thesis work aim, more generally, to contribute to the understanding of ground vibration generation under vibratory sheet pile driving. The full-scale field study was performed in Solna in May 2013. It consisted in the vibratory driving of seven sheet piles, out of which three were fitted with accelerometers. During the driving, ground vibrations were measured by accelerometers, the closest ones placed only 0.5 m from the sheet pile line. The design and installation of the soil instrumentation was innovative in as much as accelerometers were not only set on the ground surface but also at three different depths (~ 3 m, 5 m and 6 m). The analysis presented in this thesis is primarily a comparison between sheet pile vibrations and ground vibrations measured 0.5 m from the sheet pile line. The principal aspects considered in the comparison are: the influence of penetration through different soil layers, the sheet pile – soil vibration transfer efficiency, the frequency content of sheet pile and soil vibrations, and differences between toe- and shaft-generated vibrations. The main conclusions from this study are: Most of the vibration loss occurs in the near field: 90-99% of the sheet pile vibration magnitude was dispersed within 0.5 m from the driven sheet pile. Moreover, the sheet pile – soil vibration transfer efficiency was reduced for higher sheet pile acceleration levels and higher frequencies. The soil characteristics strongly influence the sheet pile vibration levels. A clear distinction could be made between "smooth" and "hard" driving, the latter being associated with an impact situation at the sheet pile toe. The focus of ground vibration studies should not only be the vertical vibrations. Indeed, the ground vibrations’ horizontal component was found to be of the same or even higher magnitude than the vertical component.
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Meyer, Natalie Jo. "Soil and plant response to slash pile burning in a ponderosa pine forest". Thesis, Montana State University, 2009. http://etd.lib.montana.edu/etd/2008/meyer/MeyerN1208.pdf.
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Slash pile burning is the most common method of forest residue disposal following ponderosa pine restoration harvests, which are intended to reduce the risk of catastrophic fire and restore the historical structure and function of forests in western Montana. The impact of high-intensity, long-duration fire (pile burning) on soil processes and plant community dynamics is not well understood. The objectives of this study were: (1) to characterize the influence of slash pile burning on soil nutrient availability, soil microbial activity, and arbuscular mycorrhizal (AM) infection; (2) to compare seeding and soil amendment effects on burn scars. In May 2006, slash piles were burned in a ponderosa pine stand near Florence, Montana and 45 scars were sampled. Soil samples were collected from three locations in each slash pile to a depth of 10 cm and characterized for available soil NH4 +-N, NO3 - -N, potentially mineralizable nitrogen (PMN), and total C and N, water-soluble PO4 3- -P, microbial biomass, and mycorrhizal inoculum potential (MIP). In the burned center, soil NH4 +-N was greatest one month post-burn and remained elevated one year later. There was no observable increase in NO3 - -N until one year post-burn. Soluble PO4 3- -P was not impacted by burning. Microbial biomass was reduced by burning and did not recover one year later. Pile burning greatly reduced MIP. In October 2006, fire scars were either seeded with native graminoids or left non-seeded, divided into subplots, and assigned to one of five treatments: control, addition of local organic matter, scarification, scarification and organic matter addition, or scarification and commercial compost addition. Soils were monitored for the previously measured soil parameters and resin-sorbed inorganic N. Scarification with organic matter amendment and scarification with compost amendment both ameliorated soil properties. Seeding most effectively increased plant cover and suppressed non-native invasive species, while scarification or scarification with organic matter amendment further improved early plant establishment. Collectively, these data help characterize the impacts of slash pile burning as a management technique in ponderosa pine forests and illustrate potential treatments for restoring burn pile scars.
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England, Melvin Gerrard. "A pile behaviour model". Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311976.
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Sekulovic, Dejan. "Identification of modulus of subgrade reaction of soils at pile/soil interface". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0015/MQ52659.pdf.
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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.
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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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McCarthy, Donald. "EMPIRICAL RELATIONSHIPS BETWEENLOAD TEST DATA AND PREDICTED COMPRESSION CAPACITY OF AUGERED CAST-IN-PLACE PILES IN PREDOMINANTLY". Master's thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2985.
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Augered Cast-In-Place (ACIP) Piles are used in areas were the loading from a superstructure exceeds the soil bearing capacity for usage of a shallow foundation. In Northwest Florida and along the Gulf Coast, ACIP piles are often utilized as foundation alternatives for multi-story condominium projects. Data from 25 compression load tests at 13 different project sites in Florida and Alabama were analyzed to determine their individual relationships between anticipated and determined compression load capacity. The anticipated capacity of the ACIP pile is routinely overestimated due to uncertainties involved with the process of estimating the compressive capacity and procedures of placing the piles; therefore, larger diameter and deeper piles are often used to offset this lack of understanding. The findings established in this study will provide a better empirical relationship between predicted behaviors and actual behaviors of ACIP piles in cohesionless soils. These conclusions will provide the engineer with a better understanding of ACIP pile behaviors and provide a more feasible approach to more accurately determine the pile-soil interaction in mostly cohesionless soils.M.S.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering MS
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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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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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Resare, Fredrik. "Analysis of an Inclined Pile in Settling Soil". Thesis, KTH, Jord- och bergmekanik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183384.
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The use of inclined piles is an efficient way to handle horizontal forces in constructions. However, if the soil settles the structural bearing capacity of each pile is reduced because of induced bending moments in the pile. There are several reasons for a soil to settle, e.g. if an embankment is built on top of a clay settlements will occur. There is currently no validated method in Sweden to analyse horizontal loading from a settling soil. In the current report a non-linear 3D finite element model is validated by a previously conducted field test and the results are compared to three different beam-spring foundations. These consist of a standard model where a subsoil reaction formulation is used, a model where the soil is considered as a distributed load, and a model with a wedge type of failure. Furthermore, a parametric study is conducted for a cohesionless material where the weight and friction angle of the soil material is varied. The standard soil reaction model yields an induced bending moment almost three times larger than the one obtained from the field test and the two other calculation methods. The latter beam-spring models should therefore be considered in practical design. These findings imply that inclined piles can be used in a far greater extent than previously expected, hence decreasing the cost for the project.Användning av lutande pålar är ett väldigt effektivt sätt att ta hand om horisontalkrafter i konstruktioner. Om marken omkring pålen sätter sig orsakas ett böjmoment i pålen som sänker den strukturella bärförmågan av pålen. För närvarande finns ingen validerad metod i Sverige för att beräkna storleken av den horisontella kraften som orsakas av sättningarna. I den här studien har en ickelinjär 3D-FEM modell validerats mot ett tidigare utfört fullskaleförsök, dessa resultat har därefter jämförts mot tre olika 2D-diskretiseringar. Den första modellen som beskrivs är den som idag används vid påldimensioneringar. De två andra modellerna är baserade på en annan brottmekanism i påltoppen där jorden istället för en fjädermodell utgörs av en utbredd last med två olika formuleringar. Vidare har en parametrisk studie utförts med en friktionsjord där vikten och friktionsvinkeln på jordmaterial varierats. Den nuvarande 2D-diskretiseringen ger ett böjmoment i pålen som är närmare tre gånger större än det i fältförsöket uppmätta och de två föreslagna beräkningsmodellerna. Ett böjmoment så stort att pålens kapacitet teoretiskt blir obefintlig enligt nuvarande beräkningsmodell.
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Salem, Talal Husain Ibrahem. "INVESTIGATION OF PILE SETUP CORRELATIONS WITH SOIL PROPERTIES". Cleveland State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=csu15037910383013.
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Bahrami, Amir. "Contributing mass of soil in pile lateral vibrations". Thesis, Curtin University, 2014. http://hdl.handle.net/20.500.11937/2429.
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Large numbers of finite element analyses are conducted using linearly elastic soil. The value of static Winkler springs stiffness is determined for soil.A general solution to elstodynamic equations of an elastic half space (soil) with a cylindrical insert (pile) is proposed. The results are interpreted as stiffness, mass and damping values of soil. The mass value is interpreted as contributing mass of soil. Stiffness values are verified with the results of FE study.
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Seymour, Geoff, i Aregai Tecle. "Impact of Slash Pile Size and Burning on Ponderosa Pine Forest Soil Physical Characteristics". Arizona-Nevada Academy of Science, 2003. http://hdl.handle.net/10150/296601.
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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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Schneider, James A. "Analysis of piezocone data for displacement pile design". University of Western Australia. School of Civil and Resource Engineeringd%695 Electronic theses, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0207.
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Due to the similarity between the geometry and full displacement installation method of a cone penetrometer and displacement pile, the axial capacity of displacement piles is often assessed using data from a cone penetration test (CPT). As there are many more factors influencing pile axial capacity than affecting CPT cone resistance, there are a wide range of CPT-based empirical design methods in use. These methods have various levels of predictive success, which usually depends upon the soil conditions, pile geometry, pile installation method, and time between installations and loading. An improved understanding of the basis and reliability of respective design methods is essential to improve the quality of predictions in the absence of site specific load test data. This thesis explores the influence of soil state and drainage conditions on piezocone penetration test (CPTU) tip resistance (qc) and penetration pore pressures (u2). For cone penetration testing identified as 'drained', factors influencing the correlation between cone tip resistance and displacement pile shaft friction in sand are investigated through (i) a review of previous research and the performance of existing design methods; (ii) centrifuge studies of piles of differing widths with measurements of local lateral stress; (iii) field tension tests at different times between installation and loading for uninstrumented driven piles with different diameters and end conditions; and (iv) field tension tests at different times between installation and loading on closed ended strain gauged jacked segmented model piles with different installation sequences. CPTU qc and u2 are primarily controlled by soil state and drainage conditions, with effective stress strength parameters and soil stiffness also influencing the measurements. The primary mechanisms identified to control the correlation between cone tip resistance and shaft friction on displacement piles are identified as; (i) the initial increase in radial stress due to soil displaced during installation of a pile; (ii) different levels of soil displacement induced by open, closed, and partially plugged piles; (iii) reduction in radial stress behind the pile tip; (iv) additional reduction in radial stress with continued pile penetration (friction fatigue); (v) changes in radial stress during loading; (vi) constant volume interface friction angle between soil and steel; and (vii) changes in the effects of the above mentioned mechanisms with time between installation and loading. The relative effect of each of these factors is investigated in this thesis.
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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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Tang, Xiaowei. "Nonlinear Numerical Methods to Analyze Ground Flow and Soil-Pile Interaction in Liquefiable Soil". 京都大学 (Kyoto University), 2004. http://hdl.handle.net/2433/134545.
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Zhou, Jialin. "Performance of Full Scale Tests of Piles in Different Soil Conditions". Thesis, Griffith University, 2018. http://hdl.handle.net/10072/381531.
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With the soaring requirement for building space in metropolises, high-rise buildings are becoming increasingly popular. Pile foundations can resist more loading through end bearing and friction resistance than can shallow foundations; hence, the use of pile foundations is more common. As a structural element that transfers the loads from upper structures into the soil layers, piles can be categorised into precast piles and cast-in-situ piles. As a result of their numerous advantages—such as convenience of construction without considering the transfer of piles, cost and schedule of construction—bored piles are the most accepted type of piles in construction projects...Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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Arta, Mahmood Reza. "The behaviour of laterally loaded two-pile groups". Thesis, Durham University, 1992. http://etheses.dur.ac.uk/6122/.
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The response of piles and two-pile groups to lateral loading has been studied by field tests and computationally. Due to the lack of field test data and because of uncertainty concerning the pile/soil system it has been suggested that further experimental studies of pile groups under lateral loading should be undertaken. The research was conducted through a series of tests on vertical single piles and two-pile groups at various spacing and pile cap overhang heights, to identify the lateral stiffness, bending moment and axial force distribution. Attempts were also made to measure the in-situ total lateral soil pressure on the pile walls. Piles were designed to behave as "long" pile since most piles used in the U.K. are long and flexible. Piles were instrumented with strain gauges for measurement of bending moments and axial forces. Field tests were conducted in a sand trench using 4.0m long piles. A stiff steel pile cap was used to connect head of the two piles firmly together. Linear elastic back analyses of single pile tests were carried out to estimate the soil modulus profile with depth. Thereafter comparisons were made between the field test results on two-pile groups, published analyses and also a three dimensional finite element analysis. Tests results showed that the lateral stiffness of a two-pile groups tends towards a limit as spacing increases. A similar result was found from predictive and finite element analyses. The ratio between the maximum pile shaft bending moment and horizontal force varied between dry and wet season, being greater in the latter. The ratio between maximum reverse bending moment and horizontal load increased as the pile spacing and the overhang increased. Similar results results were found by finite element analysis. One of the main achievements in this research was the measurement of the axial forces in the vertical piles due to lateral loading. It was found that as the pile spacing increased and pile cap overhang height decreasd the peak axial forces per unit load decreased. Similar results were obtained by three dimensional finite element analysis.
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Husein, Dima A. "Soil-Pile Interaction of Geothermal Foundation Subjected to Temperature Cycling". University of Akron / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=akron1563974820049641.
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Ramirez, Jose Manuel. "Influence of soil permeability on liquefaction-induced lateral pile response". Diss., [La Jolla] : University of California, San Diego, 2010. http://wwwlib.umi.com/cr/ucsd/fullcit?p1474550.
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Thesis (M.S.)--University of California, San Diego, 2010.Title from first page of PDF file (viewed March 31, 2010). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. 71-73).
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Lu, Chih-Wei. "Numerical Study of Soil-Pile Interaction during Earthquakes Considering Liquefaction". 京都大学 (Kyoto University), 2003. http://hdl.handle.net/2433/148518.
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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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Seward, Linda. "The effect of Continuous Flight Auger pile installation on the soil-pile interface in the Mercia Mudstone Group". Thesis, City, University of London, 2009. http://openaccess.city.ac.uk/18263/.
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The research reported in this dissertation examines the physical and chemical changes that occur to in situ soil at the soil-pile interface for continuous flight auger piles installed in the Mercia Mudstone Group. Four Continuous Flight Auger (CFA) piles were installed in the Gunthorpe Member of the Mercia Mudstone Group, central England. The effect on the soil-pile interface of overrotation of the auger during installation, and the addition of water during installation were investigated. Once the piles had been left to cure, they were excavated and returned to City University, London, with the surrounding soil. The excavated piles and soil were examined using a variety of microscopic and macroscopic techniques including inductively coupled plasma spectroscopy (ICP) and X-ray diffraction (XRD); with water contents, chemical content (ICP) and mineralogical content (XRD) tested. Plastic index and particle size distribution tests were used to show the physical effects of piling on the host soil and preliminary strength testing was carried out to provide insight into the strength characteristics of the soil surrounding the pile. In all four piles a distinct zone of remoulding was observed around the pile shaft. In each case the remoulded zone was a brown to red, clay rich layer varying between 0mm and 55mm in thickness. In almost all cases this remoulded zone had a structure and fabric which was not related to the in situ soil. Around all piles it was further noted that vertical fissures were present, and fanned out from the pile shaft in a clockwise direction. Two of the piles were installed with the addition of water. Around these piles it was noted that the remoulded layer often split into two or three distinct layers, with one of these layers often containing millimetre scale aggregations of green silt. Tests showed a higher percentage of clays present within this remoulded zone, and indicated that SiO2 (a major rock forming element and considered by some authors to be an aggregating agent within the Mercia Mudstone Group) was more abundant within remoulded than undisturbed soil. The clay fraction showed a low abundance of high swelling clays in all cases. It was concluded that installing piles within the Mercia Mudstone Group causes remoulding of the soil directly adjacent to the pile shaft. The least remoulding occurred when the pile was augered normally with no added water. All four remoulded zones contained fissures, fanning clockwise from the pile, however, these were more pronounced in the dry piles, while the wet piles had a more massive, granular texture to the remoulded zone. For all piles, except the pile which was over-rotated and installed with no added water, the percentage of clays within the remoulded zone was greater than outside the remoulded zone. This indicates that the aggregates of clays found naturally within the Mercia Mudstone Group may be split into their constituent clays during the piling process.
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Seymour, Geoff, i Aregai Tecle. "Impact of Slash Pile Burning on Physical and Chemical Characteristics of Soil in a Ponderosa Pine Forest". Arizona-Nevada Academy of Science, 2002. http://hdl.handle.net/10150/296577.
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Heron, Matthew Joseph. "Assessment of time-dependent capacity of driven piles in Ohio soils". University of Dayton / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1556303954380124.
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Adsero, Matthew E. "Effect of jet grouting on the lateral resistance of soil surrounding driven-pile foundations /". Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2381.pdf.
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Elmarakbi, Ahmed. "Width-dependent characteristics of pile/soil system subjected to lateral force". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0034/MQ62211.pdf.
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Williams, Shon Gwyn Owen. "The behaviour of an anchored sheet pile wall in granular soil". Thesis, Heriot-Watt University, 1989. http://hdl.handle.net/10399/907.
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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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Strand, Tommy, i 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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Qin, Hongyu. "Response of Pile Foundations due to Lateral Force and Soil Movements". Thesis, Griffith University, 2010. http://hdl.handle.net/10072/365515.
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This research has investigated the response of pile foundations subjected to lateral force applied directly to pile head and loadings arising from lateral soil movements of the surrounding ground. The behaviour of pile foundations subjected to lateral soil movements was studied through physical modelling with a specially designed testing apparatus. Laboratory experiments have been undertaken on a single pile embedded in progressive moving sand. A triangular loading block was used in the model tests to induce a progressive soil movement profile. Apart from eight general tests, sixteen tests were conducted on a single pile to examine the effects of the distance between the source where soil movements were induced and the pile location, the magnitude of axial load applied at pile head, the variation of loading block angle, varying combination of sliding and stable layer depths, and pile diameter on the responses of piles. The results of previously conducted pile tests with a uniform soil movement profile were compared with those of the current tests to examine the effect of soil movement profiles on the pile behaviour. Simple solutions were proposed for predicting the pile responses. They provided good estimate of the development of maximum bending moment and maximum shear force in the piles with soil movement. Importantly, the maximum bending moments induced by the soil movements were found to be linearly related to the maximum shear forces (sliding thrust), independent of the magnitude and depth of soil movement and soil movement profiles. Experiments have also been conducted on pile groups in progressive moving sand, including various pile group configurations and spacing. Both free-head and cappedhead fixity conditions have been considered. The findings show that the resistances of the piles to lateral soil movements significantly rely on their locations in a group, especially for piles arranged in a line parallel to the soil movement direction. The results of the pile group tests were compared with those of the single pile tests. Group factors were defined in terms of maximum bending moment and modulus of subgrade reaction to quantify the impact of group effect. The simple solutions developed were extended for predicting the response of individual piles in a group with soil movement. The static and cyclic responses of laterally loaded piles in cohesionless soils have been investigated as well. Guideline for estimating the design parameters for laterally loaded rigid piles in cohesionless soils were provided from extensive back calculation of measured responses of fifty-one pile tests. The elastic-plastic solutions presented by Guo (2008) were used in the back calculation. Simple expressions were presented for estimating the parameters used in the solutions. The reliability of the back calculation, the effects of the ratio of loading eccentricity to pile embedded length on the nonlinear pile response and lateral load capacity were investigated. Additionally, the apparatus was modified to apply cyclic lateral loading, with which a series of model tests were conducted on piles in dry sand under static and cyclic loadings. Analyses of the test results show that the cyclic load level has a greater impact on the pile behaviour than the number of cycles. It is noted that the gradient of the limiting force profile will decrease and the modulus of subgrade reaction will increase, after a number of unloading and reloading cycles. The induced maximum bending moment can be estimated from the applied lateral load, eccentricity of the load, and the depth at which the maximum bending moment occurs.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Engineering
Science, Environment, Engineering and Technology
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Toma, Tahsin Munir. "A model study of negative skin friction on a fixed base pile in soft clay". Thesis, Heriot-Watt University, 1989. http://hdl.handle.net/10399/919.
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In this research programme, a small-scale laboratory test was carried out to investigate the phenomenon of negative skin friction through studying the interaction between a pile and the surrounding soil and to obtain, by means of an instrumented 50mm diameter model pile, an expression for the magnitude and distribution of negative skin friction for an end-bearing pile in soft clay. The programme included measurements of pore water pressures using miniature piezometers, both vertically along the pile shaft and laterally from it, as the pattern of dissipation of this pressure controls the distribution of negative skin friction along pile length at any given time. Two testing programmes were conducted. Each testing programme consisted of applying load increments on the soil up to 90 kPa as surcharge pressures. Pore pressures, settlements and pile loads were monitored until 90% consolidation had been achieved. From test results, expressions relating the surcharge pressure and soil shear strength with the developed negative skin friction have been established. The study has been extended to include predictions of negative skin friction and pore water pressures by the use of Numerical Methods such as the Finite Element Method and the Finite Difference Method. Results obtained by these methods have been compared with those measured.
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Kan, J. H.-S. "Behaviour of laterally-loaded piles". Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383277.
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Horne, John C. "Effects of liquefaction-induced lateral spreading on pile foundations /". Thesis, Connect to this title online; UW restricted, 1996. http://hdl.handle.net/1773/10195.
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Gui, Meen-Wah. "Centrifuge and numerical modelling of pile and penetrometer in sand". Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361612.
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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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Berenguer, Todo-Bom Luis André. "Numerical modeling of soil-pile interaction considering grain breakage in finite deformations". Phd thesis, Ecole Centrale Paris, 2014. http://tel.archives-ouvertes.fr/tel-01000298.
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The analysis of pile behavior is a complex problem due to the diversity of the phenomena governing the soil behavior and particularly that of the neighboring soil. The objective of this work was to develop a valid modeling tool to evaluate piles' behavior under axial loads by developing a pertinent mechanical model supported in a robust finite element program which would successfully reproduce the soil behaviour under extreme monotonic and cyclic shear strain. This is done to allow for the numerical modelling of the installation procedure of pile foundations and continued loading of high amplitude cyclic paths. In order to model the installation phase of a monotonic, jacked or dynamic pile foundation some issues must be addressed. Finite deformations take place whilst the pile is put in place requiring an adjustment in the mechanical formulation of the model at the interface level to take into account that the small deformations (rotations and strain) hypothesis is no longer valid. Moreover, the constitutive model must take into account the physical behaviour of the soil when subjected to high order of magnitude displacements. This includes the phenomenon of grain breakage, also referred to as particle crushing, which greatly influences the volumetric behaviour of soil as thus reflecting of shear stress mobilization. The elastoplastic ECP model has therefore been enhanced by introducing an internal variable taking into account the breakage mechanism. The thermodynamic admissibility criteria are verified for the original and revised constitutive models. Both monotonic and pseudo-dynamic installation procedures were numerically simulated and the results thoroughly analysed. Finally, the cyclic shear resistance degradation at the pile shaft is a commonly occurring phenomenon during continued cyclic loading of pile foundation (friction fatigue). The constitutive modelling of this phenomenon, however, is not a straightforward matter. The stress path followed by the thin layer at the soil-pile interface level is known to be directly related to the volumetric behaviour due to the boundary conditions of the problem. A comprehensive analysis of all the components of the behaviour of soil during this stage was object of study in this work.
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Jebur, A. A. J. "An experimental and theoretical study of pile foundations embedded in sand soil". Thesis, Liverpool John Moores University, 2018. http://researchonline.ljmu.ac.uk/9211/.
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This study aimed to examine the load carrying capacity of model instrumented piles embedded in sand soil, and to develop and verify reliable, highly efficient predictive models to fully correlate the non-linear relationship of pile load-settlement behaviour using a new, self-tuning artificial intelligence (AI) approach. In addition, a new methodology has been developed, in which the most effective pile bearing capacity design parameters can be precisely determined. To achieve this, a series of comprehensive experimental pile load tests were carried out on precast concrete piles, steel closed-ended piles and steel open-ended piles, comprised of three slenderness ratios of 12, 17 and 25, using an innovative calibrated testing rig, designed and manufactured at Liverpool John Moores University. The model piles were tested in a large pile testing chamber at a range of different densities of sand; loose (18%), medium (51%) and dense (83%). It is worth noting that novel structural fibres were utilised and optimised for different volume fractions to enhance the mechanical performance of concrete piles. The obtained results revealed that the higher the values of the of the pile effective length, Lc (embedded length of pile), sand density, and the soil-pile angle of shearing resistance, the higher the axial load magnitudes to reach the yield limit. This can be attributed to the increase in the end bearing point and mobilised shaft resistance. In addition, the plastic mechanism occurring in the surrounding soil was identified as the leading cause for the presence of nonlinearity in the pile-load tests. Furthermore, a new enhanced self-tuning supervised Levenberg-Marquardt (LM) training algorithm, based on a MATLAB environment, was introduced and applied in this process. The proposed algorithm was trained after conducting a comprehensive statistical analysis, the key objectives being to identify and yield reliable information from the most effective input parameters, highlight the relative importance “Beta values” and the statistical significance “Sig values” of each model input variable (IV) on the model output. To assess the accuracy and the efficiency of the employed algorithm, different measuring performance indicators (MPI), suggested in the open literature, were utilised. Common statistical performance indexes, i.e., root mean square error (RMSE), Pearson’s moment correlation coefficient (p), coefficient of determination (R), and mean square error (MSE) for each model were determined. Based on the graphical and numerical comparisons between the experimental and predicted load-settlement values, the results revealed that the optimum models of the LM training algorithm fully characterised load-settlement response with remarkable agreement. Additionally, the proposed algorithm successfully outperformed the conventional approaches, demonstrating the feasibility of the current study. New design charts have been developed to calculate the individual contribution of the most significant pile bearing capacity design parameters “the earth pressure coefficient (K) and the bearing capacity factor (N )”. The improved approach takes into account the change in sand relative density, pile material type, and the pile slenderness ratios. It is therefore a significant improvement over most conventional design methods recommended in the existing design procedures, which do not consider the influence of the most significant parameters that govern the pile bearing capacity design process.
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Ibarra, German A. 1959. "CANTILEVER SHEET PILE ANALYSIS FOR STRATIFIED COHESIVE SOIL DEPOSITS (COMPUTER PROGRAM, SPILE)". Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276434.
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