Thèses : « Pileni »

1

Franza, Andrea. « Tunnelling and its effects on piles and piled structures ». Thesis, University of Nottingham, 2017. http://eprints.nottingham.ac.uk/39102/.

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Current needs for infrastructure and services in urban areas often require the construction of tunnels that may affect existing surface and buried structures. In general, the construction of new tunnels in the proximity of deep foundations raises concerns related to pile failure and associated structural damage (in both the superstructure and the foundation). Despite its practical importance, few studies have investigated the global tunnel-pile-structure interaction (TPSI) and, thus, engineers generally compensate for the lack of understanding with an overly conservative design approach. To provide insights into the interaction mechanisms of TPSI, this research used geotechnical centrifuge testing as the main investigation method to acquire data related to both greenfield tunnelling in sands and tunnel excavations beneath piles and piled buildings. In particular, a novel method was developed to study TPSI problems through the real-time coupling of numerical and centrifuge modelling, enhancing centrifuge modelling capabilities. Furthermore, empirical and closed-form solutions were used to study the tunnelling-induced displacement fields and simplified elastic analyses were used to provide insights into the global TPSI mechanisms. Results from the greenfield tests illustrate that ground movement prediction in sands is very complex because of soil arching effects and changes that occur as tunnels transition from relatively shallow to deep depths, resulting in highly non-linear displacement mechanisms. Results also illustrate the correlation between vertical and horizontal displacement mechanisms. In particular, the influence of soil relative density and volume loss on deformation patterns is highly dependent on the tunnel relative depth. To provide simple tools for engineering practice, empirical and closed-form solutions are proposed. Predicted ground movements provide sufficient accuracy for preliminary assessments, though limitations of these methods should be considered. The centrifuge tests on TPSI provide experimental evidence that tunnelling-induced pile displacements are affected by [i] pile installation method (displacement versus non-displacement piles), which affects the pre-tunnelling soil state and the distribution of loads between pile shaft and base, [ii] initial safety factor of the pile foundation, which is related to pile bearing capacity and superstructure self-weight, and [iii] superstructure stiffness and configuration, which results in pile load redistribution while minimising structural distortions. In addition, results show that potential for pile failure is a critical aspect for piles with relatively low initial safety factors and that pile failure may be prevented by a limited relative reduction in the pile load due to the superstructure. Finally, the importance of superstructure stiffness and self-weight on tunnelling-induced structural distortions is confirmed. Piled buildings respond critically to tunnelling beneath the pile tip depth in terms of flexural deformations. In general, it is shown that [iv] piles increase structural distortions compared to shallow foundations and that [v] the superstructure stiffness and self-weight decrease and increase the superstructure distortions resulting from tunnelling, respectively. Results are also evaluated within the modification factor approach; parametric analyses of elastic soil-pile-structure interaction are used to develop simple design charts that can be used to estimate horizontal strains and deflection ratio modification factors based on newly defined relative axial and bending stiffness parameters. The envelopes compare well with deflection ratio modification factors measured from centrifuge tests. Further research is needed to include the effects of soil plasticity, building self-weight, superstructure configuration and tunnel-structure eccentricity in these design charts. This dissertation highlights the improvements in the design of underground constructions that can be achieved by combining ground and structural engineering.

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2

Pam, Hoat Joen. « Seismic performance of prestressed concrete piles and pile-pile cap connections ». Thesis, University of Canterbury. Civil Engineering, 1987. http://hdl.handle.net/10092/7634.

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The performance, strength and ductility of prestressed concrete piles, and their connection to pile caps, subjected to severe seismic loading are investigated in this thesis. Knowledge of the strength and ductility of the pile within its embedded length in the foundation material is of importance due to the large deformations which can occur during an earthquake, particularly at the interface of hard and soft layers of foundation material. Connection details are of interest since high moments, shears and axial forces need to be transferred to pile caps during earthquake loading. Two series of tests of piles and their connections, and accompanying analyses, were conducted. Design tables and charts were derived. The first test series consisted of six full scale octagonal prestressed concrete piles, confined spirally with either Grade 275 steel or hard drawn (Grade 485) steel wire and having various confinement levels, tested under axial load and cyclic flexure. Results of the theoretical analysis were compared with the experimental data. It was found that properly detailed prestressed concrete piles without additional nonprestressed longitudinal steel can sustain large displacement ductility factors without losing their lateral load carrying capacity significantly if confined according to full ductility. The second test series consisted of six full scale octagonal piles connected to full scale reinforced pile caps. The piles were either fully or partially prestressed. Three types of pile to pile cap connection were investigated, namely the precast embedded type, the stripped pile head type, and the type where steel dowel bars are used as the connection device. Theoretical analyses were used to compare the experimental data. The connection details investigated were found to give satisfactory performance. Finally, tables and charts obtained for the pile properties are presented for design purposes. The design tables are used to assess the enhancement factors of pile cross sections within the length or at the interface of the connection at the pile cap. The design charts are used to calculate the yield curvatures as well as the available curvatures and available curvature ductility factors. Recommendations for future research are proposed to complement the work already done up to this stage.

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3

Selemetas, Dimitrios. « The response of full-scale piles and piled structures to tunnelling ». Thesis, University of Cambridge, 2006. https://www.repository.cam.ac.uk/handle/1810/251993.

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4

Lehane, Barry. « Experimental investigations of pile behaviour using instrumented field piles ». Thesis, Online version, 1992. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.283868.

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5

Maheetharan, A. « Modelling the seismic response of piles and pile groups ». Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358741.

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6

Badri, Dhuruva. « Determination of axial pile capacity of prestressed concrete cylinder piles ». [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0001449.

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7

Edde, Robert D. « Case pile wave equation analysis : CAPWAPC. Evaluation of driven piles ». Thesis, University of Ottawa (Canada), 1991. http://hdl.handle.net/10393/7587.

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One of the most important aspects of a piled foundation is the bearing capacity of the individual piles. Correct quantitative evaluation of the pile capacity during pile driving requires the use of dynamic monitoring by means of the Pile Driving Analyzer. These monitoring data are combined with a wave equation analysis and processed using a special software called CAPWAP. The CAPWAP analysis is an iterative procedure whereby the calculated force trace is adjusted to agree with the one measured. The main objective of the thesis study is to produce a statistical indication of the natural variation between the results from a CAPWAP analysis performed on blows within the same soil layer. More specifically, for three selected case histories, the natural variation is studied between contiguous blows of the pile capacity, the resistance distribution between the shaft and the toe, and of the soil dynamic parameters (quakes and damping) as determined in the CAPWAP analysis. (Abstract shortened by UMI.)

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8

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.

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9

Ayfan, Emad. « Design method for axially loaded piled raft foundation with fully mobilised friction piles ». Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209604.

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In the present work, a settlement-based method is proposed to design piled raft foundation. The proposed design method is found to be very efficient, economical and requires less calculation time. Simple software can be used to execute all the interactions and loop calculations.

Unlike methods with numerical techniques, there are practically no limitations for the number of individual piles under the raft, size of the group and the group shape or layout. It can also be applied to piles with different length or piles that are located within multi-layered soils.

The raft is designed first according to the allowable settlement that is pre-defined by the structural requirements and with the necessary factor of safety. When raft suffers excessive settlement, then the load that causes excess raft settlement beyond the required limit is to be transferred to the fully mobilised frictional piles.

The fully mobilised shaft (with no end bearing) piles are designed with factor of safety close to unity since their function is only to reduce raft settlement and since the raft has an adequate bearing capacity.

Geometry of these piles is chosen to fully mobilise their shafts capacity with low settlement level in order to comply with load/settlement requirement and reduce raft settlement to the pre-defined level.

Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

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10

Xu, Yao. « Calibration of settlement analysis models for single piles and pile groups / ». View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202006%20XUY.

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11

Wang, A. « Three dimensional finite element analysis of pile groups and piled-rafts ». Thesis, University of Manchester, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.573097.

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12

Shaul, Robert. « Wave forces on cylindrical piles and pile groups : a critical review ». Master's thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/8293.

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Includes bibliography.
This thesis is a critical review of methods of predicting wave forces on vertical piles or groups of piles. It assigns different force prediction theories to different situations or flow regimes and analyses their advantages and disadvantages. The thesis is split into two sections: Section I reviewing the force prediction methods for single piles, and Section II for groups of piles.

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13

Kennouche, Paul. « New insights into meningococcal pathogenesis : exploring the role of the major pilin PilE in the functions of type IV pili Mechanisms of meningococcal type IV pili multiple functions revealed by deep mutational scanning ». Thesis, Sorbonne Paris Cité, 2018. https://wo.app.u-paris.fr/cgi-bin/WebObjects/TheseWeb.woa/wa/show?t=1972&f=12515.

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Les pili de type IV (PT4) sont des filaments micrométriques qui exercent de multiples fonctions à la surface de nombreux procaryotes. Chez Neisseria meningitidis, les PT4 sont des homopolymères de la piline majeure PilE. Leur implication dans l'agrégation interbactérienne et l'adhésion aux cellules humaines les rend centraux dans la virulence du méningocoque. Cependant, les mécanismes permettant aux PT4 d'exercer ces diverses fonctions restent trop élusifs. Durant ce doctorat, nous avons simultanément déterminé les régions de PilE impliquées dans l'assemblage des pili, l'auto-agrégation, l'adhésion aux cellules humaines et la compétence à la transformation en utilisant la technique de deep mutational scanning. L'analyse approfondie de cette carte fonctionnelle de la séquence de la piline offre de nouvelles perspectives sur les mécanismes de fonctionnement des PT4 : tout d'abord, le domaine hyperconservé 1 de PilE est impliqué dans la régulation de la balance entre la longueur et le nombre des pili ; par ailleurs, nous avons identifié un groupe d'acides aminés électropositifs autour de la lysine 140 requis pour l'agrégation ; enfin, nous montrons l'importance de l'extrémité distale des PT4 dans l'adhésion. En résumé, ces résultats sont en faveur d'un rôle direct de PilE dans l'agrégation et l'adhésion bactérienne et identifient les domaines spécifiquement impliqués dans ces fonctions. Ces travaux ouvrent aussi de nouvelles perspectives sur la pathogénicité de Neisseria meningitidis et pourraient participer au développement de nouvelles thérapies pour combattre les pathologies provoquées par le méningocoque
Type IV pili (TFP) are multifunctional micrometer-long filaments expressed at the surface of many prokaryotes. In Neisseria meningitidis, TFP are homopolymers of the major pilin PilE. They are crucial for virulence as they mediate interbacterial aggregation and adhesion to host cells although the mechanisms behind these functions remain unclear. During this doctoral work, we simultaneously determined the regions of PilE involved in pili display, auto-aggregation and adhesion to human cells by using deep mutational scanning. Mining of this extensive functional map of the pilin sequence provides new mechanistic insights: first, the hyperconserved 1-domain of PilE was found to be involved in the balance between pili length and number; moreover, we identified an electropositive cluster of residues centered around Lysine 140 necessary for aggregation; finally, we show the importance of the tip of TFP in adhesion. Overall, these results support a direct role of PilE in aggregation and adhesion to host cells and identify these specific functional domains. This doctoral work opens up new perspectives on the pathogenicity mechanisms of Neisseria meningitidis and could help design new therapies to fight meningococcal disease

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14

Yilmaz, Beren. « An Anlaytical And Experimental Study On Piled Raft Foundations ». Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611500/index.pdf.

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Two different concepts and design procedures namely settlement reducing piles and piled raft foundations have been studied independently in this thesis. A laboratory study is conducted on model rafts with differing number of model settlement reducing piles. Pile length, pile diameter, type of soil and size of raft are kept constant and settlements are measured under sustained loading. Remolded kaolin is consolidated under controlled stresses before tests are performed in model boxes. The tests are conducted under two sustained loadings of 75 kPa and 40 kPa. 0(raft), 16 and 49 number of piles are used. During the tests, all of the skin friction is mobilized. Several tests are conducted for each combination to see the variability. It is concluded that increasing the pile number beyond an optimum value is inefficient as far as the amount of settlement is considered. Also an analytical procedure has been followed to calculate settlements with increasing number of piles. In the second part of this thesis, finite element analyse have been performed on a piled raft foundation model, using Plaxis 3D Foundation Engineering software. This analyse are supported with analytical methods. The piled raft model is loaded with 450 kPa raft pressure. The studies are conducted in two sets in which different pile lengths are used
25 m and 30 m respectively. The numbers of piles are increased from 63 to 143. All other parameters are kept constant. The results showed that again an optimum number of piles will be sufficient to reduce the settlement to the acceptable level. The analytical methods indicate a similar behavior. The comparison and results are presented in the study.

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15

Chang, Brian KF. « Simplified procedure for analysis of laterally loaded single piles and pile groups ». Thesis, University of Hawaii at Manoa, 2003. http://hdl.handle.net/10125/6970.

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Current methods for designing pile groups for lateral loading require a computer program or extensive manual computations. This research presents a spreadsheet- or calculator-amenable approach for estimating lateral deflections and maximum moments in single piles and pile groups. The approach for single piles is an extension of the characteristic load method, used for predicting deflections and moments when the pile top is at the ground surface. The proposed method applies to embedded fixed-head piles, which represents most practical situations. The resulting lateral deflections and moments are less due to the increased embedment. A simplified procedure to estimate group deflections and moments was also developed. Termed the Group Amplification Method (GAM), group amplification factors are introduced to amplify the single pile deflection and bending moment to reflect group effects. This approach provides good agreement with other generally accepted analytical tools and with values measured in load tests on groups of fixed-head piles.
x, 62 leaves

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16

Wong, Man-kie. « A study of capacity predictions for driven piles by dynamic pile testing ». Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37106120.

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Wong, Man-kie, et 黃文基. « A study of capacity predictions for driven piles by dynamic pile testing ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B37106120.

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18

Aloulou, Fathi. « Grouted tension piles under multi-directional loads governed by grout/pile interface ». Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47331.

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19

Lee, Cheol-Ju. « The influence of negative skin friction on piles and in pile groups ». Thesis, University of Cambridge, 2001. https://www.repository.cam.ac.uk/handle/1810/272078.

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20

Baxter, David. « Innovation in the design of continuous flight auger and bored displacement piles ». Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/5091.

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The field of pile design and construction in the United Kingdom is currently in a period of change. Not only are new processes and techniques being developed but also the legislative landscape is changing with the introduction of new Europe wide normative standards (BSI, 2004, 2007). This project sought to optimise pile design through better understanding and interpretation of ground conditions and of the pile-soil interaction for two pile types, continuous flight auger and bored displacement piles. Quantitative methods for interpreting and summarising previous knowledge and experience have been developed; the strata are divided into discrete bands and properties are represented with summary statistics. Experience and previous knowledge relating to the shear strength of London Clay have been quantified and presented using this approach. Furthermore, a straightforward tool has been provided for the implementation of such data into design; the previous knowledge and new site specific data are combined using Bayesian updating. Through use of this technique, the uncertainty associated with interpreting ground conditions from site data has been demonstrated to be reduced. The techniques described have been adopted into design practice within the sponsoring company. Bored displacement piles are a relatively new pile type. There is little published data or scientific understanding of the processes undergone by the soils during and after construction and the effect that these have on pile performance. This research identified the need for, and developed, a unified framework of descriptors for the various types of bored displacement pile and investigated the installation energy and performance of bored displacement piles in London Clay. The energy to construct the pile was observed to be highly variable and not directly related to capacity. Performance of bored displacement piles was observed to be similar to continuous flight auger piles of similar dimensions; typical values for the adhesion between bored displacement piles and the surrounding soil were established and these were comparable to those achieved by continuous flight auger piles. In addition, to enable the analysis of the probability of failure of a pile, the sources of variation have been investigated and the variability quantified. Besides the soil conditions, the dimensions of the pile, notably pile diameter, were found to be a significant source of variation.

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21

Stacul, Stefano [Verfasser], et Joachim [Akademischer Betreuer] Stahlmann. « Analysis of piles and piled raft foundation under horizontal load / Stefano Stacul ; Betreuer : Joachim Stahlmann ». Braunschweig : Technische Universität Braunschweig, 2018. http://d-nb.info/1175815330/34.

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Stacul, Stefano Verfasser], et Joachim [Akademischer Betreuer] [Stahlmann. « Analysis of piles and piled raft foundation under horizontal load / Stefano Stacul ; Betreuer : Joachim Stahlmann ». Braunschweig : Technische Universität Braunschweig, 2018. http://nbn-resolving.de/urn:nbn:de:gbv:084-2018061815086.

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23

So, Hin-ting Simon, et 蘇顯庭. « Comparison of pile loading test results of instrumented frictional H-piles with predictions from classical theory of pile capacityequations ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B30431657.

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24

Amer, Hetham A. Ramadan. « Effect of Wall Penetration Depth on the Behavior of Sheet Pile Walls ». University of Dayton / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1366765763.

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25

Ingeland, Rose-Marie, et Päivi Kukkonen. « Lärares erfarenheter av språkmaterialet PILEN ». Thesis, Stockholm University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8099.

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Sammanfattning

Syftet med denna studie är att undersöka lärares erfarenheter av språkmaterialet Pilen. Vi vill också belysa Pilen-materialet ur perspektiv av tidigare forskning om läs- och skrivinlärning. Vår studie bygger på en enkätundersökning som vi gjorde bland 25 lärare som använder detta undervisningsmaterial samt en observation av ett lektionspass då materialet användes. De resultat vi fick från vår enkätundersökning var övervägande positiva vad gäller barnens motivation, självkänsla och möjligheter att reflektera över sin egen inlärning. Lärarna ansåg även att det gav stora möjligheter att inkludera barn i behov av särskilt stöd i vanlig klassundervisning. Nackdelarna med materialet är att det helst kräver en extra lärarinsats, men å andra sidan behöver elever i behov av särskilt stöd inte gå ifrån till specialundervisning. Lärarna har haft svårigheter med att installera datorprogrammen eller inga licenser, men det är tekniska orsaker, som inte kan kopplas till själva materialet.

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26

Dhorajiwala, Husein. « Grundläggning med olika pålningsmetoder : En teknisk och ekonomisk studie ». Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-31004.

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This degree project compares piling methods with respect to technical and economic aspects, all affecting factors are measured as realistic as possible. The aim was to get a better understanding for piling methods used in Sweden and to work as an information tool for structural engineers. In order to get the technical aspects on piling methods literature study and interviews with structural engineers from Kadesjös Ingenjörsbyrå AB have been conducted. The case study on a residential building in Västerås was also performed. In this case study calculations for a quantity of piling methods have been made and sent for RFQs for various entrepreneurs. Subsequently piling methods have been analyzed and compared with respect to their prices. By calculating the costs of various piling methods it has been analyzed why some piling methods are more expensive than others. In a layer from soil that is free from rocks and other obstacles the concrete pile is the economically effective piling method for a residential building for both five and thirty meters. The magnificent steel pile is only 5% more expensive than the concrete pile. Note that this degree project is not a cheat sheet for the most economical pile.

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Bell, Jared Keith. « Seismic testing of existing full-scale pile-to-deck connections precast prestressed and steel piles / ». Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p1453232.

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Thesis (M.S.)--University of California, San Diego, 2008.
Title from first page of PDF file (viewed June 30, 2008). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. 85).

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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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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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30

Ercan, Anil. « Behaviour Of Pile Groups Under Lateral Loads ». Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611804/index.pdf.

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To investigate the lateral load distribution of each pile in a pile group, the bending moment distribution along the pile and the lateral group displacements with respect to pile location in the group, pile spacing, pile diameter and soil stiffness three dimensional finite element analysis were performed on 4x4 pile groups in clay. Different Elatic Modulus values, pile spacings, pile diameters and lateral load levels used in this study. In the analysis PLAXIS 3D Foundation geotechnical finite element package was used. It is found that, lateral load distribution among the piles was mainly a function of row location in the group independent from pile spacing. For a given load the leading row piles carried the greatest load. However, the trailing row piles carried almost the same loads. For a given load, bending moment values of the leading row piles were greater than the trailing row piles. On the other hand, as the spacing increased group displacements and individual pile loads decreased under the same applied load. However, this behavior was seen more clearly in the first and the second row piles. For the third and the fourth row piles, pile spacing became a less significant factor affecting the load distribution. It is also found that, pile diameter and soil stiffness are not significant factors on lateral load distribution as row location and pile spacing.

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Han, Jie. « An experimental and analytical study of the behavior of fiber-reinforced polymer piles and pile-sand interactions ». Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/20296.

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Greenwood, Steven Michael. « Analytical performance evaluation of hollow prestressed piles and pile-cap connections in the I-5 Ravenna Bridge ». Pullman, Wash. : Washington State University, 2008. http://www.dissertations.wsu.edu/Thesis/Fall2008/S_Greenwood_012608.pdf.

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Thesis (M.S. in civil engineering)--Washington State University, December 2008.
Title from PDF title page (viewed on Apr. 8, 2009). "Department of Civil and Environmental Engineering." Includes bibliographical references (p. 136-140).

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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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Marceau, Michaël. « L'adhesion mediee par les pili de neisseria meningitidis : role de la variation antigenique et de la glycosylation de la piline ». Paris 6, 1997. http://www.theses.fr/1997PA066451.

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Neisseria meningitidis, est l'agent de la meningite cerebro-spinale chez l'homme. L'adhesion aux tissus est essentielle pour la pathogenicite de n. Meningitidis. Elle permet le franchissement de la barriere hemato-meningee par la bacterie en provenance du torrent circulatoire. Les seuls attributs bacteriens indispensables a l'adhesion sont de longs appendices proteiques filamenteux : les pili. Les pili sont composes de la repetition d'une sous-unite de base : la piline. La piline est soumise a variation antigenique c'est a dire que sa structure primaire est sujette a variation au sein de la descendance d'un meme clone. Le role de la variation antigenique de la piline est sans doute d'echapper au systeme immunitaire de l'hote. Cependant, il a ete montre que les derives d'une meme souche exprimant des pilines differentes peuvent egalement aussi differents degres d'adhesion aux cellules. De fait, certains variants de piline sont responsables d'hyperadhesivite alors que d'autres ont un faible pouvoir adhesif. Les travaux que nous presentons ont permis d'identifier plusieurs mecanismes par lesquels la piline module le degre d'adhesion de la bacterie. La region carboxyterminale de la molecule a d'abord ete identifiee comme responsable de cette modulation. Les observations en microscopie electronique ont permis de montrer qu'elle etait impliquee dans un mecanisme base sur le controle de l'agregation des pili entre eux. Ce dernier permet d'augmenter les interactions bacterie-bacterie responsables elles-memes du nombre de bacteries interagissant avec les cellules. Les travaux les plus recents ont permis de caracteriser un autre mecanisme base sur la presence ou l'absence d'une modification post-traductionnelle, une glycosylation, impliquant une autre region de la piline. Nous avons montre que la piline est plus soluble en milieu acqueux lorsqu'elle est glycosylee, et que cette solubilite influe sur l'equilibre entre la piline assemblee en pili et la piline a l'etat monomerique, soluble dans le milieu. La piline possede un domaine de fixation aux cellules humaines, masque lorsque la piline prend part a l'assemblage du pilus. Le maintient par la glycosylation de la piline sous forme monomerique pourrait permettre a ce site d'interagir avec les cellules, suggerant que la piline joue un role autre que structural.

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Omer, J. R. « Numerical analysis of pile test data from instrumented large diameter bored piles formed in Keuper marl (Mercia mudstone) ». Thesis, University of South Wales, 1998. http://eprints.kingston.ac.uk/17499/.

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Alkroosh, Iyad Salim Jabor. « Modelling pile capacity and load-settlement behaviour of piles embedded in sand & ; mixed soils using artificial intelligence ». Thesis, Curtin University, 2011. http://hdl.handle.net/20.500.11937/351.

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This thesis presents the development of numerical models which are intended to be used to predict the bearing capacity and the load-settlement behaviour of pile foundations embedded in sand and mixed soils. Two artificial intelligence techniques, the gene expression programming (GEP) and the artificial neural networks (ANNs), are used to develop the models. The GEP is a developed version of genetic programming (GP). Initially, the GEP is utilized to model the bearing capacity of the bored piles, concrete driven piles and steel driven piles. The use of the GEP is extended to model the load-settlement behaviour of the piles but achieved limited success. Alternatively, the ANNs have been employed to model the load-settlement behaviour of the piles.The GEP and the ANNs are numerical modelling techniques that depend on input data to determine the structure of the model and its unknown parameters. The GEP tries to mimic the natural evolution of organisms and the ANNs tries to imitate the functions of human brain and nerve system. The two techniques have been applied in the field of geotechnical engineering and found successful in solving many problems.The data used for developing the GEP and ANN models are collected from the literature and comprise a total of 50 bored pile load tests and 58 driven pile load tests (28 concrete pile load tests and 30 steel pile load tests) as well as CPT data. The bored piles have different sizes and round shapes, with diameters ranging from 320 to 1800 mm and lengths from 6 to 27 m. The driven piles also have different sizes and shapes (i.e. circular, square and hexagonal), with diameters ranging from 250 to 660 mm and lengths from 8 to 36 m. All the information of case records in the data source is reviewed to ensure the reliability of used data.The variables that are believed to have significant effect on the bearing capacity of pile foundations are considered. They include pile diameter, embedded length, weighted average cone point resistance within tip influence zone and weighted average cone point resistance and weighted average sleeve friction along shaft.The sleeve friction values are not available in the bored piles data, so the weighted average sleeve friction along shaft is excluded from bored piles models. The models output is the pile capacity (interpreted failure load).Additional input variables are included for modelling the load-settlement behaviour of piles. They include settlement, settlement increment and current state of loadsettlement. The output is the next state of load-settlement.The data are randomly divided into two statistically consistent sets, training set for model calibration and an independent validation set for model performance verification.The predictive ability of the developed GEP model is examined via comparing the performance of the model in training and validation sets. Two performance measures are used: the mean and the coefficient of correlation. The performance of the model was also verified through conducting sensitivity analysis which aimed to determine the response of the model to the variations in the values of each input variables providing the other input variables are constant. The accuracy of the GEP model was evaluated further by comparing its performance with number of currently adopted traditional CPT-based methods. For this purpose, several ranking criteria are used and whichever method scores best is given rank 1. The GEP models, for bored and driven piles, have shown good performance in training and validation sets with high coefficient of correlation between measured and predicted values and low mean values. The results of sensitivity analysis have revealed an incremental relationship between each of the input variables and the output, pile capacity. This agrees with what is available in the geotechnical knowledge and experimental data. The results of comparison with CPT-based methods have shown that the GEP models perform well.The GEP technique is also utilized to simulate the load-settlement behaviour of the piles. Several attempts have been carried out using different input settings. The results of the favoured attempt have shown that the GEP have achieved limited success in predicting the load-settlement behaviour of the piles. Alternatively, the ANN is considered and the sequential neural network is used for modelling the load-settlement behaviour of the piles.This type of network can account for the load-settlement interdependency and has the option to feedback internally the predicted output of the current state of loadsettlement to be used as input for the next state of load-settlement.Three ANN models are developed: a model for bored piles and two models for driven piles (a model for steel and a model for concrete piles). The predictive ability of the models is verified by comparing their predictions in training and validation sets with experimental data. Statistical measures including the coefficient of correlation and the mean are used to assess the performance of the ANN models in training and validation sets. The results have revealed that the predicted load-settlement curves by ANN models are in agreement with experimental data for both of training and validation sets. The results also indicate that the ANN models have achieved high coefficient of correlation and low mean values. This indicates that the ANN models can predict the load-settlement of the piles accurately.To examine the performance of the developed ANN models further, the prediction of the models in the validation set are compared with number of load-transfer methods. The comparison is carried out first visually by comparing the load-settlement curve obtained by the ANN models and the load transfer methods with experimental curves. Secondly, is numerically by calculating the coefficient of correlation and the mean absolute percentage error between the experimental data and the compared methods for each case record. The visual comparison has shown that the ANN models are in better agreement with the experimental data than the load transfer methods. The numerical comparison also has shown that the ANN models scored the highest coefficient of correlation and lowest mean absolute percentage error for all compared case records.The developed ANN models are coded into a simple and easily executable computer program.The output of this study is very useful for designers and also for researchers who wish to apply this methodology on other problems in Geotechnical Engineering. Moreover, the result of this study can be considered applicable worldwide because its input data is collected from different regions.

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Ponížil, Cyril. « Analýza zatěžovací zkoušky piloty ». Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2017. http://www.nusl.cz/ntk/nusl-265323.

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There is ussualy used the Masopust's method to assessment the piles in Czech Republic. This method is based on statistical processing of large data set of load piles tests. Due to the using of regression coefficients this method is relatively complicated and not very transparent. Instead, foreign standards ussualy use direct the values of limit stress on the base of piles and unit friction capacity. Procedure for determining the bearing capacity of the piles is thus considerably simplified. In this thesis the Masopust's method is compared with the methods used in Germany and Austria. This comparison provides insight to the safety level that include various approaches.

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Christensen, Dustin Shaun. « Full Scale Static Lateral Load Test of a 9 Pile Group in Sand ». Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1267.pdf.

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Marshall-Jones, Zoe Victoria. « Molecular analysis of neisserial pilins ». Thesis, University of Liverpool, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369116.

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Chitra, R. « M. Radhakrishna Pillai, a study ». Madras : Dept. of Indian History, University of Madras, 1989. http://catalog.hathitrust.org/api/volumes/oclc/23803848.html.

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Snyder, Jeffrey L. « Full-Scale Lateral-Load Tests of a 3x5 Pile Group in Soft Clays and Silts ». Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd364.pdf.

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Rinne, Isabella, et Lisa Lödesjö. « Att arbeta med svenskmaterialet PILEN : - Är det ett inkluderande arbetsmaterial ? » Thesis, Mälardalen University, School of Education, Culture and Communication, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-9468.

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Lam, Joley. « Termination criteria for high-capacity jacked and driven steel H-piles in Hong Kong ». View the Table of Contents & ; Abstract, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38027811.

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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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Hatch, Cody. « Lateral Resistance of Piles Near Vertical MSE Abutment Walls ». BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4328.

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A full scale MSE wall was constructed and piles were driven at various distances behind the wall. Lateral load testing was conducted and the performance of the pile, wall, and reinforcement were measured. The piles were 12.75 inch pipe piles, and the wall was reinforced with welded wire grid reinforcement. The objective of the testing was to characterize the relationship between the lateral pile resistance and the distance of the pile behind the back face of the MSE wall. Load-displacement curves are presented for the piles located behind the wall at 66 inches (5.3 diameters), 55 inches (4.3 diameters), 41 inches (3.2 diameters), and 24 inches (1.9 diameters). The lateral resistance of the piles decreases as the spacing behind the wall decreases. The results of the testing have been matched in LPILE using p-multipliers to reduce the lateral resistance. A curve has been developed showing the variation of p-multiplier with normalized pile spacing behind the wall, including data from previous studies. The curve suggests that a p-multiplier of 1 (no reduction in lateral resistance) can be used when the normalized distance from the back face of the wall to the center of the pile is at least 4 pile diameters. The p-multiplier decreases relatively linearly for smaller spacings.

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Karlsrud, Kjell. « Prediction of load-displacement behaviour and capacity ofaxially loaded piles in clay based on analyses and interpretation of pile load test results ». Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for bygg, anlegg og transport, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-17071.

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The main objective of the work presented herein was to develop new semi-empirical design procedures for determination of bearing capacity and load-displacement response of axially loaded piles in clay. Hereunder also prediction of how the capacity will build up with time following the pile installation, primarily as a result of consolidation. A main basis for developing new procedures was the collection, detailed review and assessment of results from a series test programs carried out over the past 30 years on well instrumented piles. The data collected and reviewed include the pile installation, re-consolidation, and loading phases. The pile instrumentation includes measurement of the distribution of loads or shaft friction, pore pressure and earth pressure along the pile shafts. The soil conditions range from soft NC clays with undrained shear strength down to about 15 kPa, to very stiff and high OCR clays with undrained shear strength up to about 500 kPa. The plasticity index of the clays mostly lies in range 10 to 60 %. The test piles range from small scale model piles with diameter down to 36 mm and length down to 1- 2 m, to large scale piles with diameter up to 800 mm and length up 71 m. In addition to these fully instrumented pile tests, some recent large scale tests on non-instrumented piles are also reviewed and included as basis for developing the new proposed design procedures. Two new procedures for predicting ultimate shaft friction are proposed, respectively a so-called α- and β approach. They tie the local ultimate shaft friction along a pile to the “true” undisturbed in-situ undrained strength of the clay as determined from Direct Simple Shear Tests, the in-situ vertical effective stress, the overconsolidation ratio, and the plasticity index of the clay. No clear evidence is found of effects of pile diameter, length or stiffness on the local ultimate shaft friction, or whether the pile is open-or closed- ended. A moderate effect of pile length or flexibility on the total ultimate pile capacity will still come out of the proposed t-z curves, which include some postpeak reduction. A brief review and summary is also given of measured effects of cyclic loads on the axial capacity and pile head displacements of piles. It is concluded that this issue can be well accounted for by analytical or numerical procedures already in existence. A semi – empirical analytical procedure, based on linear radial consolidation theory, is proposed for predicting the time required for re-consolidation and “set-up” of the ultimate shaft friction. The main input parameters are the in-situ permeability and virgin modulus number (or virgin compression index) of the undisturbed clay. The same basic formula and correlations were found applicable to both open- and closed- ended or partially plugging piles. For design purposes it is very important to recognise that the time for full set-up can easily be a factor of 10 longer for a closed– ended pile than for an ideal nonplugging open- ended pile. It was also an objective to study how well the measured pile response during installation, re-consolidation and pile loading could be predicted from analytical and numerical models. Although such procedures can give very valuable insight, there is still a way to go before they can correctly capture all relevant elements of the pile response. The greatest need for improvement is to establish a better understanding of how the severe disturbance and strains induced by the pile installation affects the basic stress-strain, strength-, and volumetric compressibility- characteristics of the clay, depending on the level of induced shear strains as function of radial distance from the pile wall.

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SOUZA, Ruiter da Silva. « Análise dos fatores de interação entre estacas em radier estaqueado : comparação entre duas ferramentas numéricas ». Universidade Federal de Goiás, 2010. http://repositorio.bc.ufg.br/tede/handle/tde/1320.

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Made available in DSpace on 2014-07-29T15:18:18Z (GMT). No. of bitstreams: 1 Dissertacao de Mestrado Ruiter da S Souza 2010.pdf: 3795319 bytes, checksum: ce03329bc9c991e1ebf4ddcb63aeada9 (MD5) Previous issue date: 2010-08-06
Researches done in the last decades concerning the settlement of pile foundations, mainly when it s considered as piled raft, had greatly evolved due the progress on computational tools used in the analysis. However, the tridimensional analysis of a pile foundation, taking into account the interaction between your components (soil, piles and raft), is still a very complex problem. To achieve a satisfactory evaluation of the interaction between the foundation's elements, numerical tools like Boundary Elements Method (B.E.M.), Finite Elements Method (F.E.M.) and hybrid methods, that combines two or more methods, are available, each one with its own advantages and drawbacks. The F.E.M. is considered in the technical sphere as the most complete method for piled raft evaluation, but your high processing time requirements, required in the analyses, prevents your usual employment. For this reason, a necessity to compare this methodology with others, as the one used in simplified programs, that decreases the processing time, arises. To evaluate the results proximity achieved by different methods, this work presents the simulation of some pile blocks, calculated as piled rafts, employing two programs (GARP and DIANA) to foresee your behavior. GARP is a hybrid program which analyzes the raft by using F.E.M. and the pilessoil set by B.E.M. and, like the other programs of same kind published in the literature, it doesn't take the influence between intermediary piles into account for the analysis. DIANA is a purely finite elements program, based on the displacement method. Thus, the main objective of this work was to evaluate how taking or not the interaction factor between piles into consideration can modify the predictions of settlement and pile loads. For that, it was evaluated how the attribution or omission of these interaction factors into specific regions that comprise some or all the piles, modifies the predictions of the foundation performance and makes them approximate or distant from the F.E.M. results, considering the most exact one. The way that the simplified programs handle the problem, makes the settlement previsions excessive. To contour this and to make the settlement results from the simplified methods become close of the expected ones from F.E.M., the discovered way was the imposition of a limit in the distance used in the calculation of the piles interaction, based on the raft's size and the number of piles in that case. Many examples of pile rafts in homogeneous soils was evaluated and the maximum distance limits of interaction between piles that generated the best results in the settlement prevision are shown. In all examples, the effect of raft stiffness in these results was also taken into account. Also, an analysis case in heterogeneous soil was done, where it was observed that this fact also interferes in the piles interaction process. For pile load predictions, the results were distinct from settlement prediction and was noticed that not limiting the maximum interaction distance between the piles generated the best previsions.
As pesquisas realizadas nas últimas décadas sobre o recalque de fundações estaqueadas, principalmente quando a mesma é considerada como radier estaqueado, tiveram grande evolução devido ao avanço das ferramentas computacionais utilizadas nas análises. Porém, a análise tridimensional de uma fundação estaqueada considerando a interação entre seus componentes (solo, estacas e radier), continua sendo um problema muito complexo. Para uma avaliação satisfatória da interação entre os elementos da fundação, ferramentas numéricas como o Método de Elementos de Contorno (M.E.C.), o Método de Elementos Finitos (M.E.F.) e métodos híbridos, que combinam dois ou mais métodos, estão disponíveis, cada uma com suas vantagens e desvantagens. O M.E.F. é considerado pelo meio técnico como o método mais completo para avaliação de um radier estaqueado, mas seu alto tempo de processamento, tomado em grande parte das análises, impede que seu uso se torne mais corriqueiro. Com isso, surge a necessidade de se comparar essa metodologia com outras, como a usada em programas simplificados, que diminuem o tempo de processamento. Para a avaliação da proximidade dos resultados determinados por diferentes métodos, esta dissertação apresenta a simulação de alguns blocos de estacas, calculados como radiers estaqueados, utilizando dois programas para prever seus comportamentos, o GARP e o DIANA. O GARP é um programa híbrido que analisa o radier pelo M.E.F. e o conjunto estacas-solo pelo M.E.C. e, como os demais programas do gênero divulgados na literatura, não considera a influência de estacas intermediárias na análise. O DIANA é um programa de elementos finitos puro, baseado no método dos deslocamentos. Assim, o principal objetivo deste trabalho foi avaliar como a consideração ou não dos fatores de interação entre estacas pode modificar a previsão de recalques e carga nas estacas. Para isso, foi avaliado como a atribuição ou a omissão dos fatores de interação dentro de regiões específicas, que englobam algumas ou todas as estacas, modificam a previsão do desempenho da fundação e fazem com que se aproximem ou se distanciem dos resultados do M.E.F., considerado o mais exato. A forma como os programas simplificados tratam o problema faz com que suas previsões de recalques sejam excessivas. Para contornar este fato e fazer com que os resultados de recalques dos métodos simplificados sejam mais próximos dos previstos pelo M.E.F., a forma encontrada foi a imposição de um limite na distância usada no cálculo da interação entre as estacas, dependendo do tamanho do radier e número de estacas do caso. Vários exemplos de radiers estaqueados em solos homogêneos foram estudados e são apresentados os limites máximos da distância de interação entre estacas que originaram melhores resultados na previsão do recalque. Em todos os exemplos avaliou-se o efeito da rigidez do radier nestes resultados. Também foi analisado um caso em solo heterogêneo, onde se observou que este fato também interfere no processo de interação entre estacas. Para a previsão de carga nas estacas o resultado foi distinto da previsão de recalques e observou-se que a não limitação da distância máxima de interação entre estacas foi o que resultou em melhores previsões.

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Wong, Eric Yi-wai. « Behaviour of large-diameter bored pile groups with defects / ». View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202004%20WONG.

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Maschke, Sebastian [Verfasser]. « Naturstoffe aus endophytischen Pilzen / Sebastian Maschke ». Bielefeld : Universitätsbibliothek Bielefeld, 2019. http://d-nb.info/1199005231/34.

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Wang, Yaohui. « Behavior of socketed steel H-piles ». Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B36761400.

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