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1
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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BORGA, PAULA CECILIA. "DESIGN PARAMETER FOR EVALUATION OF PILE FOUNDATION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2001. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=2037@1.
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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR<br>Os projetos de capacidade de suporte de estacas estão
baseados em dados de ensaio de campo de maneira direta ou
indireta. Devido a sua praticidade, os métodos empíricos
são amplamente utilizados. No Brasil os métodos de Decourt e
Quaresma (1978, 1982) e de Aoki e Velloso (1975) se
destacam. Este trabalho procura avaliar o uso de dados de
SPT e CPT para estimativa de parâmetros geotécnicos
necessários na previsão de capacidade de suporte de estacas
através de métodos teóricos. São apresentadas e avaliadas
formulações empíricas de estimativa de parâmetros para
materiais granulares e materiais argilosos. Outro elemento
importante na previsão da capacidade de suporte é o estado
de tensões atuante em torno da estaca que é analisado
através de considerações a respeito do coeficiente de
empuxo. Finalmente, são mostrados alguns resultados de
provas de carga para a análise da seleção de parâmetros e
do estado de tensões, além de uma avaliação dos métodos
empíricos de previsão de capacidade de suporte.<br>The main objective of this thesis is to discuss the
applicability of in-situ tests like the Standard
Penetration Test (SPT) and the Cone Penetration Test (CPT)
to determine directly the design parameters to predict the
bearing capacity of pile foundations. In case it will be
considered the use of empirical correlation to indicate the
mechanical properties of the soil in terms of shear
resistance, and the application of these values directly in
the classic formulation based on the theory of equilibrium
limit to evaluate distinctly the shaft and the base
resistance of piles. Adaptations of these values will be
proceeded considering aspects related with the non-linear
behavior of the soil; the mechanism of load transfer and
the influence of the constructive aspects.The results
obtained through this new methodology will be compared with
experimental results, obtained from static and dynamic load
tests and also with other empiric procedures that use the
results obtained from in-situ tests to evaluate directly the
bearing capacity of deep foundations.
3
Ha, Inho. "Seismic performance of CIDH pile supported foundation /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2002. http://wwwlib.umi.com/cr/ucsd/fullcit?p3059909.
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Niazi, Fawad Sulaman. "Static axial pile foundation response using seismic piezocone data." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/52195.
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Ever since the use of cone penetration testing (CPT) in geotechnical site investigations, efforts have been made to correlate its readings with the components of static axial pile capacity: unit base resistance (qb) and unit shaft resistance (fp). Broadly, the pile capacity analysis from CPT data can be accomplished via two main approaches: rational (or indirect) methods, and direct methods. The rational methods require a two-step approach, whereby CPT data are first used to provide assessments of geoparameters that are further utilized as input values within a selected analytical framework to enable the evaluation of the pile capacity components. In contrast, direct CPT methods use the measured penetrometer readings by scaling relationships or algorithms in a single-step process to obtain fp and qb for full-size piling foundations. The evolution of the CPT from mechanical to electrical to electronic versions and single-channel readings (i.e., measured tip resistance, qc) to the piezocone penetration test (CPTu), that provides three readings of point stress (qt), sleeve friction (fs), and porewater pressure (u1 or u2), has resulted in the concurrent development of multiple CPT-based geotechnical pile design methods. It is noted, however, that current CPT-based methods focus only on an estimate of "axial pile capacity", corresponding to a limiting load or force at full mobilization.
A more comprehensive approach is sought herein utilizing the CPT readings towards producing a complete nonlinear load-displacement-capacity (Q-w-Qcap) on axial pile response. In particular, the seismic cone penetration test (SCPT) provides the profile of shear wave velocity (Vs) that determines the fundamental small-strain shear modulus: Gmax = gt?Vs2, where gt = total mass density of soil. With the penetrometer readings useful in assessing foundation capacity, the stiffness Gmax finds application within elastic continuum solutions towards evaluating the load-displacement (Q-w) response.
In this study, a concise review of the deep foundation systems is presented, including pile types and characteristics, various arrangements of axial pile load testing in static mode, and interpretations of the load test data. In addition a comprehensive state-of-the-art review of CPT-based rational and direct methods of pile capacity evaluations is compiled. It is recognized that the direct methods offer more convenience in their straightforward approach in estimation of the pile capacity. The piezocone-based UniCone direct method proposed by Eslami and Fellenius (1997) is selected for further refinements, as it utilizes all three CPT readings in its design formulations. Concerning the analysis of pile deformations under axial loading, a brief review covers designs employing empirical formulations, analytical solutions, load-transfer (t-z) methods, numerical simulations, variational approaches, and those using hybrid methods. Specifically, the analytical elastic solution by Randolph and Wroth (1978; 1979) is covered in more detail since it is simple and convenient in application with extended applications to uplift and bidirectional O-cell types of loadings. This elastic approach also serves well in modeling a stacked pile solution for layered soil profiles. The last part of the review covers various shear modulus reduction schemes, since evaluation of the applicable stiffnesses is considered to be the most delicate phase in the nonlinear Q-w response analysis of axially loaded piles. It is identified that the most appropriate scheme applicable to static axial loading of pile foundations is the one that can be derived from the back-analyses of actual load tests within the framework of analytical elastic solution.
In order to conduct a comprehensive research study on the axial Q-w-Qcap response of deep foundations from CPT readings, a large database is compiled. This includes 330 case records of pile load tests at 70 sites from 5 continents and 19 different countries of the world, where pile foundations were load tested under top-down compression or top-applied uplift (tension) loading, or both, or by bi-directional Osterberg cell setups. All test sites had been investigated using CPT soundings; in most cases by the preferred SCPTu that provides all four readings from the same sounding: qt, fs, u2, and Vs. In a few cases, sites were subjected to CPT or CPTu and the profiles of shear wave velocities were obtained by other field geophysical techniques, otherwise by empirical estimations.
Results of the new correlation efforts are offered to derive coefficients Cse for shaft component and Cte for base component of the axial pile capacity from CPTu data. The UniCone type of soil classification chart is refined by delineating 11 soil sub-zones along with their respective Cse, in contrast to the 5 zones originally proposed. The CPT material index, Ic (Robertson, 2009) is then used to establish direct correlations linking Cse vs. Ic and Cte vs. Ic. Statistical relationships offer continuous functions for estimating the coefficients over a wide range of Ic values, thereby eliminating the need for use of the soil classification chart as well as improving the reliability in the evaluations of fp and qb. The effects of the pile loading direction (compression vs. uplift) and loading rate are also incorporated in the proposed design formulations.
New sets of shear stiffness reduction curves are developed from the back-analysis of pile load tests and Gmax profiles obtained from the SCPT data. Alternative functions formats are provided in terms of hyperbolic tangent expressions or exponential curves, developed as normalized shear stiffness (G/Gmax) vs. logarithm of percent pseudo-strain (gp = w/d, where w = pile displacement and d = pile diameter). These charts offer convenience in the axial Q-w analysis of different pile categories within the framework of analytical elastic solution. The results also account for the plasticity characteristics of the soil formations within the database.
A stacked pile model for Q-w analysis is presented in which certain adaptations are proposed in the elastic continuum solution. These adaptations enable plotting of separate modulus reduction curves (G/Gmax vs. gp) as function of depth for each layer, and treating pile as a stack of smaller pile segments embedded in a multi-layered soil media. The solution can be used to address the question of progressive failure with depth in a multi-layer soil media that exhibits nonlinear soil stiffness response.
Finally, the closed-from analytical elastic pile solution for predicting the Q-w response is decoupled and modified to account for different setup cases and multi-stage loading of bi-directional O-cell tests. The decoupling accounts for separate assessments of the response to axial loading for different segments of pile shaft and different stages of loading, while the modifications include: (1) reduced maximum radius of influence for the upward displacements of the upper shaft segment, and (2) modeling the non-linear ground stiffness from the back-analysis of a well-documented dataset of O-cell load tests.
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Eastman, Ryan S. "Experimental Investigation of Steel Pipe Pile to Concrete Cap Connections." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2628.
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Piles are often used to resist vertical and lateral loads when shallow foundations are inadequate or uneconomical. A critical part in designing pile foundations is the pile-to-cap connection. When a moment resisting connection is desired, reinforcement is typically used between the pile and the cap. A pile-to-cap connection with sufficient pile embedment depth, however, may provide similar results. One model that is currently used to determine the capacity of a pile-to-cap connection was developed by Marcakis and Mitchell for steel members embedded in concrete. This model considers an embedment mechanism that resists rotation at the connection. Recent testing has shown, however, that this model is conservative and that additional mechanisms contribute to the strength of the connection. An experimental study was conducted to investigate pile-to-cap connections for pipe piles without reinforcement. Three pile-to-cap specimens with varying pile embedment depth were loaded laterally to failure. The results from the testing confirm that pile-to-cap connections with shallow pile embedment depth have significant stiffness. An improved model was developed to estimate elastic and ultimate capacities of embedded connections. In addition to the embedment mechanism used by Marcakis and Mitchell, this model includes a bearing mechanism at the end of the pile. For pile-to-cap connections with a large pile bearing area to pile embedment depth ratio, this bearing mechanism provides more strength than the embedment mechanism. For pile-to-cap connections with a small pile bearing area to pile embedment depth ratio, this bearing mechanism has little contribution to the strength of the connection.
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Dou, Huaren. "Response of pile foundation under simulated earthquake loading." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29935.
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An extensive series of small scale model tests on single piles embedded in sand were carried out using the hydraulic gradient similitude (HGS) technique simulating earthquake
loading. The dynamic loading was applied using the shake table at the University of British Columbia. The HGS method employs a high hydraulic gradient across the sand sample to increase the effective stresses in the model simulating full scale stress conditions
in the field. Since the soil behaviour is stress level dependent, the HGS technique is considered to provide a realistic simulation of the full scale pile foundation behaviour.
Free vibration tests were performed to study the natural frequency response of soil-pile system, and the behaviour of the system stiffness and damping at different soil stress levels. The boundary effects are evaluated and discussed. The dynamic behaviour of pile response and soil-pile interaction were investigated over a range of shaking intensities at various exciting frequencies. The dynamic p-y curves were derived from the test data and found to be highly nonlinear and hysteretic at shallow depth. Approximate linear elastic p-y response occurs at greater depth. The test results show an insignificant and negligible influence of loading cycles for dense sand. The backbone p-y curves for sand recommended by the American Petroleum Institute (API) were computed and compared with the experimental data, and were seen to be in poor agreement. The near field hysteretic damping was estimated from the p-y hysteretic loops.
The tests create a data base against which the theoretical and numerical approaches can be assessed. Predictions of the response of pile and superstructure to dynamic loading were made using different procedures of constructing p-y curves. The analyses show, generally, a reasonable agreement with test data.<br>Applied Science, Faculty of<br>Civil Engineering, Department of<br>Graduate
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Leung, Yat Fai. "Foundation optimisation and its application to pile reuse." Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608973.
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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.<p>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.<p>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. <p>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.<p>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. <p><br>Doctorat en Sciences de l'ingénieur<br>info:eu-repo/semantics/nonPublished
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Yip, Hau-ling Emily. "GIS for ground investigation in bored pile foundation works /." View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31683551.
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Yip, Hau-ling Emily, and 葉巧玲. "GIS for ground investigation in bored pile foundation works." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45007950.
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Iliadelis, Dimitrios. "Effect of deep excavation on an adjacent pile foundation." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/34597.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2006.<br>Includes bibliographical references (leaf 70).<br>The thesis studies the behavior of single axially loaded pile located close to a 30m deep braced excavation in Marine Clay corresponding to site conditions of the Kallang formation in Singapore. Parametric analyses were carried out, using non linear three-dimensional finite element methods (with Plaxis Foundation 3-D), comparing different pile lengths (17m, 30m and 42m) cross sections (solid concrete sections of 0.4m and 1.Om diameter) and proximity to the excavation (2m-10m). The results focus on the development of horizontal deformations and bending moments due to the excavation process. The computed results for end-bearing piles (42m long) are compared with semi-empirical design methods proposed by Poulos and Chen (1997). In general, this design method substantially underestimates the computed wall deflections and bending moments. This result confirms the importance of site-specific analyses for these types of complex soil-structure interactions.<br>by Dimitrios Iliadelis.<br>M.Eng.
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Yang, Haoran. "Pile foundation design for shear wall with coupling beams." OpenSIUC, 2020. https://opensiuc.lib.siu.edu/theses/2768.
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The reinforced concrete shear wall is one of the most commonly used lateral load resisting structural components in reinforced concrete buildings. The purpose of this study is to analyze the two independent shear walls, which are connected with coupling beams in the presence of lateral loads. When a lateral load acts on one side of the shear walls, due to the highly rigid nature of adjacent shear walls, most of the stress concentrated on the foundation beam, coupling beams, and foundation piles. Different types of foundation beam design and different foundation pile arrangement could affect the strength of the overall structure. This study is focused on improving the design of the foundation mat and foundation pile arrangement to mitigate the design risks associated with the coupling wall structure.This thesis uses STAAD.Pro to establish 16 variety of computer models of different mat foundations and different foundation pile arrangement to analyze seismic loads. The results reveal that a continuous intense, rigid foundation beam is essential for the coupled shear wall structure, and the appropriate pile arrangement can also reduce the bending moment and shear force in the foundation beam and coupling beam.
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Begaj, Qerimi Leonora. "Geotechnical centrifuge model testing for pile foundation re-use." Thesis, City, University of London, 2009. http://openaccess.city.ac.uk/17452/.
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In recent years development is at premium in many European cities. With life cycles of 25-30 years of buildings in financial cities and about 40 years in regional centres the ground is becoming more and more congested with redundant foundations. As the underground development of services and infrastructure already confines the location of building foundations, redundant foundations only add to this problem. The research described in this thesis, using centrifuge model testing, describes how the existing pile foundations in overconsolidated clay are likely to behave when their loading conditions are changed by unloading caused by demolition and subsequent reloading. This is done with the view to re-use the existing pile foundations for the new redevelopments. The influence of the new foundations on the existing foundations is also described. By re-using the foundations, the use of raw materials is reduced, the energy consummation for construction is reduced, the volume of soil from foundation construction is eliminated and the construction time significantly reduced, consequently reducing the whole costing of a structure. Experimental data was obtained from series of twenty one centrifuge model tests undertaken at 60g. The geometry of the model was such that it was possible to test two sets of foundations with each test. The performance of piles in overconsolidated clay when subjected to load/unload/reload cycles and the influence of supplementary piles used to achieve the required capacity were investigated. The model tests include comparison of the behaviour of bored piles when supplemented with mini piles of different length, number and spacing (centre to centre distance between the mini piles and the existing centre pile). An increase in capacity was observed when single piles were subjected to load cycles. It was found that this increase in capacity is dependent on the previous loading conditions of the pile. The behaviour of enhanced piles was characterised using a single pile test as datum test. The influence of these novel pile groups on the existing pile was dependent on the number, length of the mini-piles in the group and centre to centre spacing between the existing and new pile foundation.
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Garanito, Laurinda Aguiar Gomes. "Decision support system case base reasoning applied to pile foundation." Thesis, University of Macau, 1997. http://umaclib3.umac.mo/record=b1447773.
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Ivarsson, Kristoffer. "Pile foundation, calculation method and design tables according to Eurocode." Thesis, Linköpings universitet, Medie- och Informationsteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-94549.
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Because of the transition to a common standard for building regulations in Europe called Eurocodes, there is a need to update old reports that was written when old national standards were in use. A pile foundation is needed if the ground beneath a building does not have enough loadbearing capacity. The function of the pile cap is to distribute the load from the above construction on to the piles in the ground. The goal of this thesis is to create design tables with a number of type caps that can be use to quickly get a grip of the size, quantity of reinforcement steel and loadbearing capacity of the cap without the need to do any calculations. To create the values for the design tables the cantilever truss model was used. The truss is made up of the strut between the pile head-compression zone under the wall/pillar and the tie that is the reinforcement steel. The choice of this model makes it relatively simple to calculate the height and loadbearing capacity for the cap.The model from the theory part of the thesis is further explained by a calculation example that shows how the model has been implemented to create the design tables. The work with this thesis has been carried out at WSP and has it’s grounds in an handbook that they have there.
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Fatemi-Ardakani, B. "A contribution to the analysis of pile-supported raft foundation." Thesis, University of Southampton, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379319.
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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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Jiang, Yunyi. "FOOTING FIXITY OF BRIDGE PIER WITH END-BEARING PILE FOUNDATION." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/dissertations/1478.
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The degree of footing fixity G value of a column is a parameter which represents the rotation restraint at the base of a column. By using G values, the effective length factor K of the column can be calculated. The K value is used to check if the effect of slenderness needs to be considered for the column design. Moreover, the rotation of structural members is a major factor in determining the deflection of structures. The magnitude of structure deflection due to the rotation and elastic deformation are used to check if the second-order effect (P-delta effect) needs to be considered. When large axial loaded compression members, like bridge piers, are under lateral load impacts, the rotation at the base of the pier may cause a significant effect on the lateral deflection of the pier. However, traditionally the computation of slenderness ratio and the structure deflection due to the lateral loads is carried out by considering that the pier footing is rigidly fixed on the ground. AASHTO recognized the significance of the footing fixity effect on bridge piers and recommended an approach to account those considerations and suggested some footing fixity G values for different footing conditions. The purpose of this study is to verify the accuracy of the G values recommended by AASHTO for the pier footing on multiple rows of end-bearing piles case. A comprehensive study using 20 models derived from the pier-pile design example presented by FHWA is developed for the finite element analysis using computer software. In order to investigate the difference of G values for different pile foundations, these models are generated using various pile lengths, soil contents, pile arrangements and pile head boundary conditions. Also, the computations of the slenderness effect check, pier deflections and the G values obtained from finite element models are provided for the comparisons with that recommended by AASHTO.
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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.<br>M.S.<br>Department of Civil and Environmental Engineering<br>Engineering and Computer Science<br>Civil Engineering MS
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Tedesco, Giacomo. ""Offshore tower or platform foundations: numerical analysis of a laterally loaded single pile or pile group in soft clay and analysis of actions on a jacket structure"." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6802/.
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Laterally loaded piles are a typical situation for a large number of cases in which deep foundations are used. Dissertation herein reported, is a focus upon the numerical simulation of laterally loaded piles. In the first chapter the best model settings are largely discussed, so a clear idea about the effects of interface adoption, model dimension, refinement cluster and mesh coarseness is reached. At a second stage, there are three distinct parametric analyses, in which the model response sensibility is studied for variation of interface reduction factor, Eps50 and tensile cut-off. In addition, the adoption of an advanced soil model is analysed (NGI-ADP). This was done in order to use the complex behaviour (different undrained shear strengths are involved) that governs the resisting process of clay under short time static loads. Once set a definitive model, a series of analyses has been carried out with the objective of defining the resistance-deflection (P-y) curves for Plaxis3D (2013) data. Major results of a large number of comparisons made with curves from API (America Petroleum Institute) recommendation are that the empirical curves have almost the same ultimate resistance but a bigger initial stiffness. In the second part of the thesis a simplified structural preliminary design of a jacket structure has been carried out to evaluate the environmental forces that act on it and on its piles foundation. Finally, pile lateral response is studied using the empirical curves.
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Richardson, Sarah. "In-Situ Testing of a Carbon/Epoxy IsoTruss Reinforced Concrete Foundation Pile." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1280.pdf.
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Holba, Radek. "Estakáda přes vodní nádrž Hričov." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240184.
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Idea of this diploma thesis is comparison of different diameters of piles which are used for bridge foundation. Diameters of piles are 1200 and 1500 mm in this case. Diploma thesis is about technical implementation, financial comparison. In outset you can read about possibilities of bridge foundation on water surface. In the end of this thesis there is described technological process of foundation for bridge across the dam Hričov.
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Wu, Xingyi. "Three-Dimensional Finite Element Analysis of the Pile Foundation Behavior in Unsaturated Expansive Soil." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42028.
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Expansive soils, which are widely referred to as problematic soils are extensively found in many countries of the world, especially in semi-arid and arid regions. Several billions of dollars are spent annually for maintenance or for repairs to the structures constructed with and within expansive soils. The major problems of expansive soils can be attributed to the volume changes associated with the alternate wetting and drying conditions due to the influence of environmental factors. Pile foundations have been widely accepted by practicing engineers as a reasonably good solution to reduce the damages to the structures constructed on expansive soils. Typically, piles foundations are extended through the active layer of expansive soil to reach the bedrock or placed on a soil-bearing stratum of good quality. Such a design and construction approach typically facilitates pile foundations to safely carry the loads from the superstructures and reduce the settlement. However, in many scenarios, damages associated with the pile foundations are due to the expansion of the soil that is predominantly in the active zone that contributes to the pile uplift. Such a behavior can be attributed to the water infiltration into the expansive soil, which is a key factor that is associated with the soil swelling. Due to this phenomenon, expansive soil typically moves upward with respect to the pile. This generates extra positive friction on the pile because of the relative deformation. If the superstructure is light or the applied normal stress on the head of the piles is not significant, it is likely that there will be an uplift of the pile contributing to the damage of the superstructure.
In conventional engineering practice, the traditional design methods that include the rigid pile method and the elastic pile method are the most acceptable in pile foundation design. These methods are typically based on a computational technique that uses simplified assumptions with respect to soil and water content profile and the stiffness and shear strength properties. In other words, the traditional design method has limitations, as they do not take account of the complex hydromechanical behavior of the in-situ expansive soils. With the recent developments, it is possible to alleviate these limitations by using numerical modeling techniques such as finite element methods. In this thesis, a three-dimensional finite element method was used to study the hydro-mechanical behavior of a single pile in expansive soils during the infiltration process.
In this thesis, a coupled hydro-mechanical model for the unsaturated expansive soil is implemented into Abaqus software for analysis of the behavior of single piles in expansive soils during water infiltration. A rigorous continuum mechanics based approach in terms of two independent stress state variables; namely, net normal stress and suction are used to form two three-dimensional constitutive surfaces for describing the changes in the void ratio and water content of unsaturated expansive soils. The elasticity parameters for soil structure and water content in unsaturated soil were obtained by differentiating the mathematical equations of constitutive surfaces. The seepage and stress-deformation of expansive soil are described by the coupled hydro-mechanical model and the Darcy’s law. To develop the subroutines, the coupled hydro-mechanical model is transferred into the coupled thermal-mechanical model. Five user-material subroutines are used in this program. The user-defined field subroutine (USDFILD) in Abaqus is used to change and transfer parameters. Three subroutines including user-defined material subroutine (UMAT), user-defined thermal material subroutine (UMATHT), and user-defined thermal expansion subroutine (UEXPAN) are developed and used to calculate the stress-deformation, the hydraulic behavior, and the expansion strain, respectively. Except for the coupled hydro-mechanical model of unsaturated expansive soils, a soil-structure interface model is implemented into the user-defined friction behavior subroutine (FRIC) to calculate the friction between soil and pile. The program is verified by using an experimental study on a single pile in Regina clay. The results show that for the single pile in expansive soil under a vertical load, water infiltration can cause a reduction in the pile shaft friction. More pile head load is transferred to the pile at greater depth, which increases the pile head settlement and pile base resistance. In future, the proposed method can also be extended for verification of other case studies from the literature. In addition, complex scenarios can be investigated to understand the behavior of piles in expansive soils.
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Chiluwal, Sundar. "Numerical Modeling of Helical Pile-to-Foundation Connections subjected to Monotonic and Cyclic Loads." University of Toledo / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1576021464589307.
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Korec, Michael. "Založení nové a sanované podpěry "Starého mostu" přes Dunaj v Bratislavě." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227604.
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The thesis is focused on the reconnstruction of the "Old Bridge“ in Bratislava. Part of the reconstruction is the foundations of a new pier and redevelopment of an existing pier. The introduction provides an overview of methods used for the foundations within the river and from there onwards, the most suitable method haas been selected. The piers foundation is designed in several variants, coupled with the drawings. In conclusion, the variants were compared and the most suitable one was selected.
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Ondráček, Jaroslav. "Zajištění stavební jámy a založení objektu SONO v Brně." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225421.
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It is project of securing foundation pit and foundation for SONO building realized in Brno in Veveří street. It is required to desing economical and safety construction.A calculation was performed by program FINE GEO 5 - Student version.
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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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Höglund, Madicken, and Marcus Larsson. "Grundförstärkning med pålar i berg : I befintlig konstruktion med begränsat utrymme." Thesis, KTH, Byggteknik och design, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-287735.
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This study has been done in order to examine which type of pile, pile driving- and waterproofing methodsare most suited for an existing building. A building that will undergo an extensive reinforcement of itsfoundation.The study has been made in regard to the following conditions:● Different types of clay soil (Cohesion soil)● Underlying rock structure with heavy incline (8° slope)● Sensitive environment for vibrations and ground displacements● Limited accessibility (Room and maximum weight)● Compressive and tensile forces● Pool (Water environment)To answer the questions of statement a scientific literature study, interview with a foundation expert,calculations in sizing, but also time and cost analysis has been conducted. A site visit to an object ofreference, Nya Krav Himmerfjärdsverket, occurred where a reconstruction of an existing building withextensive work of reinforcement to its’ foundation was in progress.The steel pipe pile with anchor and steel core pile are the best pile types in such conditions as compressiveand tensile forces, clay soil with underlying inclined rock bed, limited accessibility and sensitivesurrounding environment. Which pile type, pile driving- and waterproofing methods that are most suited forsuch conditions is different for each project. The steel core pile is more suitable for higher loads, rockstructures in incline and when verification of load capacity is not needed. At the same time the steel pipepile is more suited when the underlying rock bed is far below ground level, where you would need manypile elements and joints. In addition, the steel pipe pile is suitable for buildings with a complex loaddistribution, where a greater number of piles with lower load capacities is needed in order to satisfy this.The best pile driving method for drilling in sensitive environment is the water equipped down-the-hole(DTH) drill. This drilling method is gentle to surrounding piles in existing building.In order to minimise the risk of water penetration and then expand the life span of the construction, use ofa combination of different waterproofing systems is to prefer when waterproofing pile heads or pilefoundations.
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Bohn, Cécilia. "Serviceability and safety in the design of rigid inclusions and combined pile-raft foundations." Thesis, Paris Est, 2015. http://www.theses.fr/2015PEST1096/document.
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Les inclusions rigides sont un concept récent développé dans le prolongement des fondations mixtes, avec un matelas de transfert de charges entre les colonnes et la structure. Des méthodes de calculs et des concepts de sécurité existent pour ces systèmes combinés, notamment en France où le module pressiométrique mesuré et les recommandations ASIRI (IREX 2012) pour les inclusions rigides sont utilisés. Le dimensionnement classique des pieux basé sur une simple vérification de la portance des colonnes isolées ne peut pas être appliqué à ces systèmes combinés. Les tassements peuvent être plus importants du fait de la part significative de charge reprise par le sol. Le présent travail est une contribution au développement des méthodes de calcul et de dimensionnement en déplacement (préconisé par l'Eurocode 7, EN 1997-1 2004) pour les systèmes combinés sous charge verticale, en particulier au niveau international où des mesures in situ de module de sol ne sont généralement pas disponibles. Les éventuelles particularités de ces systèmes, notamment la sensibilité de colonnes non renforcées de petit diamètre, devaient également être examinées. La méthode de transfert de charge (“load transfer method”, LTM) est identifiée comme un outil d'ingénieur particulièrement adapté au calcul des systèmes combinés présentant une géométrie relativement simple. L'interaction sol-colonne en frottement et en pointe est définie par des courbes de transfert de charge (ou courbes “t-z” et “q-z”). Les méthodes en milieu continu comme la méthode des éléments finis sont à réserver en général aux cas complexes. Le comportement non-linéaire des semelles est examiné sur la base de mesures obtenues dans la littérature. Cette étude aboutit à la proposition d'une courbe charge-tassement hyperbolique pour les semelles. Cette courbe de mobilisation est définie de sorte qu'il y ait concordance avec la méthode linéaire habituelle pour un tiers de la charge ultime de la semelle. Le comportement de pieux isolés est étudié avec de nombreux essais de chargement instrumentés et non-instrumentés pour différents types de pieux et de sol. Une alternative aux courbes de transfert de charge selon Frank et Zhao (1982), basées sur le module pressiométrique, est recherchée. Des courbes de transfert de charge de type racine cubique et hyperbolique sont proposées pour tous types de pieux et de sol. La raideur des courbes proposées dépend d'une bonne estimation des valeurs ultimes de frottement et de résistance de pointe. Au contraire, la raideur initiale des courbes de Frank et Zhao est entièrement définie par le module pressiométrique, ce qui permet d'éviter des erreurs en termes de raideur. Les courbes de mobilisation proposées pour les fondations superficielles et pour les pieux sont combinées et étendues au cas des systèmes combinés. Cette méthode est implémentée comme option LTM dans le programme KID (Keller company 2015). Les prévisions avec le modèle proposé sont en très bonne adéquation avec les mesures effectuées sur 3 sites documentés dans la littérature. Une étude paramétrique montre une transition continue entre la fondation mixte et les inclusions rigides et une possibilité d'optimisation avec une diminution significative des efforts dans les colonnes et dans la fondation superficielle si un matelas est utilisé. En complément, une comparaison avec des calculs en éléments finis en 3D dans un cas théorique de semelle sur colonnes confirme que la méthode de transfert de charge développée est très performante pour des géométries simples. Une analyse de sensibilité est effectuée avec des modèles éléments finis axisymmétriques et 3D avec Plaxis (2013, 2014). Les imperfections géométriques ont principalement une incidence sur l'intégrité structurelle des colonnes non-armées de faible diamètre. Cependant, ces effets sont atténués dans les systèmes combinés en comparaison avec la colonne isolée du fait des possibilités de redistribution des charges dans le système<br>Rigid inclusions represent a further development of combined pile-raft foundations, comprising a load transfer platform between the columns and the structure. Calculation methods and design concepts are available for such combined systems in particular in France, based on measured pressuremeter modulus values and on the French recommendations ASIRI for rigid inclusions (IREX 2012). The conventional pile design consisting only of a bearing capacity check for the individual column cannot be applied to such combined systems. The expected settlements may be larger due to a significant load proportion supported by the soil. The present work contributes to the development of displacement-based calculation methods (advocated by the Eurocode 7, EN 1997-1 2004) and design methods for combined systems under vertical loads, in particular on an international level where in general no in situ soil modulus values are measured. Possible particularities of such systems, like the sensitivity of unreinforced small-diameter columns, also had to be investigated. The load transfer method (LTM) is identified as a straightforward engineering tool for the calculation of combined systems with relatively simple geometries. The soil-column interaction in terms of skin friction and tip resistance is described by deformation-dependent load transfer curves (or “t-z” and “q-z” curves). Continuum methods like the finite element method should be preferred only for complex cases in general. The non-linear load-settlement behaviour of single footings up to failure is analysed based on measurements given in the literature. This yields the proposal of a hyperbolic load-settlement curve for footings. This mobilization curve is defined in a way to match the linear usual method for one third of the footing ultimate load. The behaviour of single piles is investigated based on numerous available instrumented and non-instrumented pile load tests with different pile and soil types. A reliable alternative to the load transfer curves after Frank and Zhao (1982), which are based on the pressuremeter modulus, is sought. Cubic root and hyperbolic axial load transfer curves are proposed for all pile and ground types. The stiffness accuracy of the proposed curves depends on an accurate estimation of the ultimate skin friction and tip resistance values. On the contrary, the initial stiffness of the Frank and Zhao curves is fully described by the pressuremeter modulus, avoiding thus errors in the stiffness. The proposed mobilization curves for the shallow and pile foundation behaviours are combined and extended for all combined systems. The proposed method is implemented as the LTM option into the software KID (Keller company 2015). The prediction with the developed model matches very well the measurements made for 3 different cases from the literature. A parametric study shows a smooth transition between the combined pile-raft foundation case and the rigid inclusion case and a potential for optimisation with a significant reduction of the internal forces in the columns and in the rigid slab when a load transfer platform is used. In addition, a comparison with 3D finite element calculations for a theoretical footing case with columns confirms that the developed load transfer method is very reliable for simple geometries. Sensitivity investigations using the axisymmetric and 3D finite element method with Plaxis (2013, 2014) are performed. Geometrical imperfections impact mainly the structural integrity of small-diameter unreinforced columns. However, these effects are reduced in combined systems compared to the single column case due to the possibility of redistribution of the loads within the system
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Sui, T., C. Zhang, D.-S. Jeng, et al. "Wave-induced seabed residual response and liquefaction around a mono-pile foundation with various embedded depth." Elsevier, 2018. http://hdl.handle.net/10454/17990.
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Yes<br>Wave-induced seabed instability caused by the residual liquefaction of seabed may threaten the safety of an offshore foundation. Most previous studies have focused on the structure that sits on the seabed surface (e.g., breakwater and pipeline), a few studies investigate the structure embedded into the seabed (e.g. a mono-pile). In this study, by considering the inertial terms of pore fluid and soil skeleton, a three-dimensional (3D) integrated model for the wave-induced seabed residual response around a mono-pile is developed. The model is validated with five experimental tests available in the literature. The proposed model is then applied to investigate the spatial and temporal pattern of pore pressure accumulation as well as the 3D liquefaction zone around a mono-pile. The numerical simulation shows that the residual pore pressure in front of a pile is larger than that at the rear, and the seabed residual response would be underestimated if the inertial terms of pore fluid and soil skeleton are neglected. The result also shows that the maximum residual liquefaction depth will increase with the increase of the embedded depth of the pile.<br>This work was supported by the Fundamental Research Funds for the Central Universities [2017B15814], the International Postdoctoral Exchange Fellowship Program [20170014], National Science Foundation for Distinguished Young Scholars [Grant No. 51425901], Fundamental Research Funds for the Central Universities (2017B21514), Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province (2018SS02), Natural Science Foundation of Jiangsu Province [Grant No. BK20161509] and Open Foundation of State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University [Project No: 2016491011].
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Aguilar, Julio. "The use of mini-pile anchors to resist uplift forces in lightweight structures." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001828.
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Toufigh, Vahid. "Testing and Evaluation of Confined Polymer Concrete Pile with Carbon Fiber Sleeve." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/293492.
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The goal of this research is to investigate the behavior of polymer concrete confined with a carbon fiber sleeve used as a pile foundation. To evaluate the behavior of a confined polymer concrete pile in this research, four steps was considered. The first step of this investigation considered the mix design of polymer concrete, polymer concrete is a new material which is a combination of epoxy resin and aggregate. Instead of using a traditional mix of cement and water to make concrete, epoxy resin is used. Three dissimilar varieties of aggregate are mixed with different ratios in order to reach the maximum bulk density to obtain the maximum strength. After discovering the optimum ratio which gives the maximum bulk density, several samples of the aggregate are mixed with different ratios of epoxy resin. Next, the samples are investigated in a compression test to observe which ratios have the maximum strength and this ratio is used for a polymer concrete mix design to create a pile foundation. The pile is a built using a cast in place method and confined with a sleeve of carbon fiber. The second part of this investigation determined the structural mechanical properties of confined polymer concrete pile material. The unconfined and confined polymer concrete was tested in compression to determine compressive strength and stress-strain behavior. Similar tests were conducted on unconfined and confined cement concrete for comparison between these materials. Additional tension tests were conducted on unconfined polymer concrete. Then, a carbon fiber sleeve was tested in compression test to determine tensile strength and tension stress-strain behavior. After these tests, the confined polymer concrete is modeled in the computer program MATTCAD which is used to calculate the theoretical bending moment capacity and load-displacement curve. Finally, the confined polymer concrete is tested with the MTS 311 Load Frame in three point load flexure test to determine the experimentally bending moment capacity, load-displacement curve and compare with theoretical results. Confined polymer concrete was tested in one and two way cyclic loading to observe the ductility behavior of this material as laterally loaded piles and compared with cement concrete results in cyclic loading. The third part of this investigation determined the geotechnical mechanical properties of confined polymer concrete pile material. Cyclic Multi Degree of Freedom (CYMDOF) device was used to determine interface reaction and friction angle between confined polymer concrete and soil with interface shear test theory method. Furthermore, the same device was used to determine the friction angle of soil with direct shear test theory, and compare the friction angle results together. The last part of this investigation considered the behavior of different sized confined polymer concrete pile in different types of soil. A confined polymer concrete pile was modeled into PLAXIS and OPENSEES PL computer software to analysis pile in axial load and lateral load respectively. Furthermore, a cement concrete pile was modeled with similar software and conditions to compare these two materials.
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Strand, Tommy, and Johannes Severin. "Soil-Structure Interaction of Pile Groups for High-Speed Railway Bridges." Thesis, KTH, Bro- och stålbyggnad, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231413.
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Pérez-Herreros, Jesús. "Dynamic soil-structure interaction of pile foundations : experimental and numerical study." Thesis, Ecole centrale de Nantes, 2020. http://www.theses.fr/2020ECDN0002.
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La réponse dynamique d’une structure supportée par des fondations profondes constitue un problème complexe d’Interaction Sol-Structure (ISS). Sous chargement sismique, les pieux sont soumis à la sollicitation imposée par le sol (interaction cinématique) et aux forces d’inertie transmises par la superstructure (interaction inertielle). Le dimensionnement des fondations profondes soumises à des sollicitations sismiques est souvent réalisé au moyen de méthodes conservatrices visant à assurer que les fondations ne soient pas endommagées. La plupart de ces méthodes considèrent le comportement de la fondation élastique linéaire et par conséquent la capacité de la fondation à dissiper de l’énergie du fait des mécanismes non-linéaires est négligée. Cette approche était justifiée dans le passé en raison du manque d’informations sur le comportement non-linéaire des fondations et de l’absence d’outils numériques adaptés. De telles limitations deviennent de plus en plus obsolètes, puisqu’un nombre pertinent de résultats expérimentaux et numériques sont maintenant disponibles, ainsi que de nouvelles méthodes de conception (Pecker et al. 2012). Dans cette thèse, le comportement des pieux isolés et des groupes de pieux sous chargement sismique est étudié avec une approche couplant l’expérimental et le numérique. Des essais dynamiques en centrifugeuse sont effectués avec un sol stratifié, plusieurs configurations de fondations et une série de séismes et sollicitations sinusoïdales. Des calculs non-linéaires aux éléments finis sont également effectués et comparés aux résultats expérimentaux afin d’étudier la capacité des modèles numériques à reproduire de manière satisfaisante la réponse non-linéaire des fondations. Un nouveau macroélément pour les groupes de pieux sous chargement sismique est proposé et validé numériquement. Le macroélément permet de prendre en compte les effets de groupe et leur variation avec la fréquence de sollicitation (interaction pieu-sol-pieu) ainsi que la non-linéarité développée dans le système. Le nouveau macroélément est enfin utilisé pour effectuer une analyse dynamique incrémentale (IDA) du pylône centrale d’un pont à haubans<br>The 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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Forni, Fabio. "Investigating the axial response of pile foundations for offshore wind turbines." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
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I crescenti problemi legati ai cambiamenti climatici rendono l'impiego delle energie rinnovabili sempre più interessante.
In questa ottica, in Germania si sta pianificando di aumentare la produzione di energia pulita attraverso lo sfruttamento dell’energia eolica. Nuovi impianti di turbine eoliche sono previsti nel Mare del Nord in acque medio profonde (25-45m) dove la parte immersa della struttura della turbina eolica (chiamata sottostruttura) è spesso costituita da una struttura jacket (traliccio) o tripod (a treppiedi). Questo tipo di sottostrutture trasmettono principalmente carichi assiali alle fondazioni (in genere fondazioni su palo), e il carico a trazione è la forza che maggiormente ne influenza il dimensionamento.
Molte compagnie energetiche tedesche sono interessate a migliorare l’efficienza e i costi dei loro impianti eolici e, per questo, incaricano università ed istituti di ricerca (come il Fraunhofer IWES) per indagarne gli aspetti, come ad esempio il comportamento delle fondazioni offshore.
All’autore di questa tesi è stata data l’opportunità di studiare e lavorare al Fraunhofer IWES e perciò questa tesi tratterà del compramento di pali caricati assialmente e staticamente pensati per sottostrutture jacket o tripod per turbine eoliche.
Nello studio effettuato per questa tesi, i dati seprimentali, ottenuti da una campagna sperimentale condotta (in larga scala 1:10 1:5) su pali infissi in terreno sabbioso, sono confrontati attraverso l’impiego delle load-transfer curves (funzioni che descrivono il comportamento d’interfaccia palosuolo) usando sia un’approccio classico (fornito dal metodo di calcolo API Main Text) sia approcci più recenti (dati dai metodi di calcolo CPT).
Uno script Matlab creato appositamente dall’autore di questa tesi riesce ad implementare 11 diversi tipi di load-transfer curves. Il lavoro di tesi si conclude con un esempio pratico in grado di fornire un’idea di come questo script può essere usato nella progettazione.
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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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Theland, Freddie. "Prediction and experimental validation of dynamic soil-structure interaction of an end-bearing pile foundation in soft clay." Licentiate thesis, KTH, Bro- och stålbyggnad, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291021.
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In the built environment, human activities such as railway and road traffic, constructionworks or industrial manufacturing can give rise to ground borne vibrations. Such vibrations become a concern in urban areas as they can cause human discomfort or disruption of vibration sensitive equipment in buildings. In Sweden, geological formations of soft clay soils overlying till and a high quality bedrock are encountered in densely populated areas, which are soil conditions that are prone to high levels of ground borne vibrations. Under such soil conditions, end-bearing piles are often used in the design of building foundations. The dynamic response of a building is governed by the interaction between the soil and the foundation. It is therefore essential that models used for vibration predictions are able to capture the dynamic soil-structure interaction of pile foundations. The purpose of this thesis is to experimentally and numerically investigate dynamic soil-structure interaction of an end-bearing pile group in clay by constructing a test foundation of realistic dimensions. The small-strain properties in a shallow clay deposit are estimated using different site investigation and laboratory methods. The results are synthesised into a representative soil model to compute the free-field surface response, which is validated with vibration measurements performed at the site. It is found that detailed information regarding material damping in the clay and the topmost soil layer both have a profound influence on the predicted surface response, especially with an increasing distance from the source. Dynamic impedances of four end-bearing concrete piles driven at the site are measured. Pile-soil-pile interaction is investigated by measuring the response of the neighbour piles when one of the piles in the group is excited. The square pile group is subsequently joined in a concrete cap and measurements of the impedances of the pilegroup and acceleration measurements within the piles at depth are performed. A numerical model based on the identified soil properties is implemented and validated by the measurements. A good agreement between the predicted and measured responses and impedances of the pile group foundation is found, establishing confidence in the ability to predict the dynamic characteristics of end-bearing pile foundations under the studied soil conditions.<br>Mänsklig verksamhet i urbana miljöer så som väg- och järnvägstrafik, byggnation eller maskindrift inom industri kan ge upphov till vibrationer som sprider sig via marken i närområdet. Dessa vibrationer kan ge upphov till kännbara vibrationer eller påverka vibrationskänslig utrustning i byggnader. I Sverige förekommer ofta mjuka lerjordar ovanpå berg, och inte sällan i tätbebyggda områden. Under sådana jordförhållanden används ofta spetsbärande pålar för grundläggning av byggnader. Det dynamiska verkningssättet för byggnader är beroende av interaktionen mellan jorden och byggnadens grund. Det är därför viktigt att modeller som används för vibrationsanalys i byggnader kan beskriva denna interaktion mellan jord och byggnadsfundament. Syftet med denna avhandling är att experimentellt och via numeriska modeller studera dynamisk jord-struktur-interaktion av ett spetsbärande pålfundament i lera. Jordensmekaniska egenskaper vid små töjningar utvärderas för en lerjord som är avsatt på morän och berg genom både fältförsök och laboratorieanalyser av prover. Informationen kombineras för att konstruera en lagerförd jordmodell av platsen för att beräkna jordens dynamiska respons till följd av en punktlast. Modellen valideras med vibrationsmätningar som utförts på platsen. Studien visar att detaljerad information angående lerans materialdämpning och de mekaniska egenskaperna av jordens översta lager har en stor inverkan på förutsägelser av jordens dynamiska respons vid ytan, speciellt vid stora avstånd från vibrationskällan. Experimentella tester utförs för att mäta dynamiska impedanser av fyra slagna spetsbärande betongpålar. Interaktionen mellan pålarna utvärderas genom att utföra mätningarav de omgivande pålarnas respons till följd av excitering av en påle. Pålgruppen sammanfogas därefter i ett betongfundament och impedanserna samt accelerationer inuti pålarna uppmäts. En numerisk modell baserad på de identifierade mekaniska egenskaperna av jorden upprättas och valideras genom mätningarna. De numeriska resultaten är i god överensstämmelse med de uppmätta vilket styrker användningen av numeriska modeller för att förutsäga interaktionen mellan jord och spetsbärandepålar under de studerade jordförhållandena.<br><p>QC 20210302</p>
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Yuksekol, Umit Taner. "A Simple Assessment Of Lateral Pier Response Of Standard Highway Bridges On Pile Foundations." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/3/12608135/index.pdf.
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Group of piles are widely used deep foundation systems to resist lateral and vertical loads. Seismic and static performance of pile groups mostly depend on soil type, pile spacing and pier rigidity.
Not many pile lateral load tests have been performed due to high costs. Advanced and complex analytical methods were developed over the years to assess nonlinear lateral pile response. This research is conducted aiming at developing a practical analysis method to verify the lateral performance of pile groups and its effect on overall response of bridge utilizing the available pile lateral load test data. Empirical constants derived from evaluation of lateral load tests are used in a simple formulation to define the nonlinear behavior of the pile-soil system. An analysis guideline is established to model the nonlinear soil-bridge interaction by the help of a general purpose structural analysis program comprising recommendations for various cases. Results of the proposed method is compared to the results of industry accepted advanced methods using response spectrum and nonlinear time history analyses to assess the suitability of this new application. According to the analysis results, proposed simple method can be used as an effective analysis tool for the determination of response of the superstructure.
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Adsero, Matthew E. "Impact of Jet Grouting on the Lateral Strength of Soil Surrounding Driven Pile Foundations." BYU ScholarsArchive, 2008. https://scholarsarchive.byu.edu/etd/1378.
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Jet grouting was used to strengthen the soft soil surrounding the piles and the pile cap of two full-scale driven pile foundations. Soilcrete columns, created by jet grouting, were placed underneath the pile cap and surrounding the piles of the first foundation. Two rows of soilcrete columns were placed around the perimeter of one-side of the second. All of the jet grouting took place after construction of the pile caps. Laboratory testing of the soilcrete slurry showed the columns as having a design unconfined compressive strength of 550-650 psi, compared with the native soil strength of only 6-8 psi (850-1150 psf). Lateral loading of the pile foundation was then performed on these foundations. The results of this test were compared with a similar test performed on the same foundations under native soil conditions. The total lateral capacity of the pile foundation treated underneath the pile cap was increased by 500 kips, which equals an increase of 175%. The total lateral capacity of the pile foundation treated adjacent to the pile cap was 150%. Results of testing suggest that each of the jet-grout treated zones displaced as a rigid block. A majority of the increased lateral resistance came from the passive soil resistance acting on the face of the blocks and the adhesive soil resistance acting on the sides and bottom of the block as it displaced through the native soil. The remaining soil resistance, not accounted for by the passive and adhesive soil resistance, can potentially be attributed to increased soil pile interaction, which is predicted from the decrease in pile head rotation during loading following soil treatment.
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Jayasinghe, Laddu Bhagya. "Blast response and vulnerability assessment of piled foundations." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/71184/1/Laddu%20Bhagya_Jayasinghe_Thesis.pdf.
Full textAbstract:
This research treated the response of pile foundations to blast loads. The influence of important parameters was investigated. The research techniques and the results will enable safer design of pile foundations that are vulnerable to blast loads.
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Nordlöf, Anders, and Danny Holmboe. "Pile subjected to lateral load : Analytical hand calculation implemented by programming." Thesis, KTH, Byggteknik och design, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302548.
Full textAbstract:
The official recommendations in geotechnical engineering are according to Swedish practice to install inclined driven piles in order to resist external horizontal loads, which usually consist of windloads. These loads gets counteracted by utilizing the pile's axial load-bearing capacity, however when designing a foundation the use of inclined piles has proven to be problematic from a number of different perspectives. This has made both engineers as well as contractors long for a solution where the piles instead are allowed to be installed vertically, which could be made possible by utilizing the lateral bearing capacity of the pile which occurs in connection with lateral resistance during pile-soil interaction. The present day knowledge about such an engineering procedure in Sweden has proven to be limited and consists mainly of one governing document, namely report 101 published by the Commission on Pile Research. The aim of our study is to test and evaluate the method in report 101 based on a number of different load cases related to lateral load effects during pile-soil interaction. An analytical method reproduced from the Commission on Pile Research's report has been implemented with help of Mathcad, a computer software for reuse of mathematical calculations. Decisive parameters that distinguish the different load cases have included external load impact in pile head, mechanical strength properties of friction or cohesive soil, along with cross-sectional dimensions and reinforcement content of piles etc. The results differed significantly depending on the loadcase, a majority of the given answers were also perceived as unreliable and in a number of load cases the method also failed to obtain an analytical solution. Our conclusion is that it is doubtful whether the elastoplastic method presented in report 101 in the end in practice benefits the engineer tasked with designing, this stands in stark contrast to an increasing demand for easily accessible knowledge within its field.<br>Pålar i samband med grundläggning har sedan en tid tillbaka enligt svensk praxis installerats snedslagna, detta för att med hjälp av pålens axiella bärförmåga motstå yttre horisontell lastpåverkan till följd av exempelvis vindlaster. Att snedställa pålar har visat sig vara problematiskt ur ett flertal olika perspektiv, en lösning som både konstruktörer och entreprenörer efterlängtat är att pålarna istället tillåts installeras rakställda. Detta skulle vara möjligt genom att nyttja pålens transversella bärförmåga som uppstår i samband med sidomotstånd vid interaktion påle-jord. Kunskap kring ett sådant dimensioneringsförfarande i Sverige idag har visat sig vara begränsad och till stor del bestå av ett styrande dokument, nämligen rapport 101 utgiven av Pålkommissionen. I denna studie har en analytisk handberäkningsmetod som återges ur Pålkommissionens rapport implementerats i beräkningsprogrammet Mathcad, detta i syfte att testa och utvärdera metoden utifrån ett flertal olika belastningsfall relaterade till transversell lastpåverkan vid interaktion påle-jord. Avgörande parametrar som skiljt de olika belastningsfallen åt har bl.a. utgjorts av hållfasthetsegenskaper hos friktion- eller kohesionsjord, tvärsnittsdimensioner och armeringsinnehåll hos påle, yttre lastpåverkan i påltopp. Resultaten skiljde sig åt markant beroende på typ av belastningsfall där en majoritet av svaren upplevdes som icke tillförlitliga och till ett flertal olika fall, utifrån vårt försök till implementering, klarade metoden heller inte av att erhålla någon analytisk lösning. Vi finner det därför svårt att tro att den elastoplastiska metoden som återges i rapport 101 i slutändan kommer till någon direkt praktisk nytta, vilket står i tvär kontrast mot ett uppenbart behov där lättillgänglig kunskap inom området efterfrågas.
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Králík, Michal. "Návrh založení dálničního mostu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-392075.
Full textAbstract:
Topic of this master`s thesis is founding of the hightway bridge, which is located between Lipník and Bělotín. Thesis is aimed for creating shallow foundation and foundation on piles and choosing which option is better. All evaluations have been made without specialized software and than compared with GEO5 results. Better solution will be completed with procedure for construction and drawing documentation.
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SALIBA, FERNANDO PORTUGAL MAIA. "HYDROGEOTECHNICAL EVALUATION OF THE FOUNDATION OF #5 WASTE PILE AT ANDRADE`S MINE: BELA VISTA DE MINAS (MINAS GERAIS)." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=10680@1.
Full textAbstract:
COMPANHIA VALE DO RIO DOCE<br>O presente trabalho concentra-se na caracterização
geológica-geotécnica e
hidrogeotécnica de uma pilha de estéril temporária,
proveniente de rocha
itabirítica, e de seu entorno, a fim de apresentar as
possíveis condicionantes
geradoras das elevadas pressões hidrostáticas medidas na
fundação desta pilha.
Com base nesta caracterização, criou-se um modelo
hidrogeológico das condições
de escoamento da água subterrânea pelo material estéril e
pelas regiões adjacentes
desta pilha, utilizando os programas computacionais SlideÒ
e VisualModflowÒ.
Em ambos os resultados apresentados pelos modelos
computacionais, observou-se
que a sub-pressão existente na fundação da pilha de
estéril está diretamente
associada a dois fatores: (i) aos condicionantes
geológicos do local e (ii) ao índice
pluviométrico do ano de 2005.<br>This study focuses on the geological, geotechnical and
hydrogeotechnical
characterization of a temporary waste pile, made of
itabiritc rock, and of its
surrounding area, and presents possible causes for the
high pore pressures
measured at the waste pile foundations. Based on this
characterization, a computer
models of this scenario were developed using both Slide
and VisualModFlow
softwares. In both cases, results indicate that the high
pore pressures are directly
related to two main causes: (1) to local geological
conditions and boundaries and
(2) to high rainfall rate recorded in 2005.
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Walsh, James Matthew. "Full-Scale Lateral Load Test of a 3x5 Pile Group in Sand." BYU ScholarsArchive, 2005. https://scholarsarchive.byu.edu/etd/605.
Full textAbstract:
Although it is well established that spacing of piles within a pile group influences the lateral load resistance of that group, additional research is needed to better understand trends for large pile groups (greater than three rows) and for groups in sand. A 15-pile group in a 3x5 configuration situated in sand was laterally loaded and data were collected to derive p-multipliers. A single pile separate from the 15-pile group was loaded for comparison. Results were compared to those of a similar test in clays. The load resisted by the single pile was greater than the average load resisted by each pile in the pile group. While the loads resisted by the first row of piles (i.e. the only row deflected away from all other rows of piles) were approximately equal to that resisted by the single pile, following rows resisted increasingly less load up through the fourth row. The fifth row consistently resisted more than the fourth row. The pile group in sand resisted much higher loads than did the pile group in clay. Maximum bending moments appeared largest in first row piles. For all deflection levels, first row moments seemed slightly smaller than those measured in the single pile. Maximum bending moments for the second through fifth rows appeared consistently lower than those of the first row at the same deflection. First row moments achieved in the group in sand appeared larger than those achieved in the group in clay at the same deflections, while bending moments normalized by associated loads appeared nearly equal regardless of soil type. Group effects became more influential at higher deflections, manifest by lower stiffness per pile. The single pile test was modeled using LPILE Plus, version 4.0. Soil parameters in LPILE were adjusted until a good match between measured and computed responses was obtained. This refined soil profile was then used to model the 15-pile group in GROUP, version 4.0. User-defined p-multipliers were selected to match GROUP calculated results with actual measured results. For the first loading cycle, p-multipliers were found to be 1.0, 0.5, 0.35, 0.3, and 0.4 for the first through fifth rows, respectively. For the tenth loading, p-multipliers were found to be 1.0, 0.6, 0.4, 0.37, and 0.4 for the first through fifth rows, respectively. Design curves suggested by Rollins et al. (2005) appear appropriate for Rows 1 and 2 while curves specified by AASHTO (2000) appear appropriate for subsequent rows.
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Sutman, Melis. "Thermo-Mechanical Behavior of Energy Piles: Full-Scale Field Testing and Numerical Modeling." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/82438.
Full textAbstract:
Energy piles are deep foundation elements designed to utilize near-surface geothermal
energy, while at the same time serve as foundations for buildings. The use of energy piles for
geothermal heat exchange has been steadily increasing during the last decade, yet there are
still pending questions on their thermo-mechanical behavior. The change in temperature
along energy piles, resulting from their employment in heat exchange operations, causes axial
displacements, thermally induced axial stresses and changes in mobilized shaft resistance
which may have possible effects on their behavior. In order to investigate these effects, an
extensive field test program, including conventional pile load tests and application of
heating-cooling cycles was conducted on three energy piles during a period of six weeks.
Temperature changes were applied to the test piles with and without maintained mechanical
loads to investigate the effects of structural loads on energy piles. Moreover, the lengths of
the test piles were determined to represent different end-restraining conditions at the toe.
Various sensors were installed to monitor the strain and temperature changes along the test
piles. Axial stress and shaft resistance profiles inferred from the field test data along with the
driven conclusions are presented herein for all three test piles. It is inferred from the field test
results that changes in temperature results in thermally induced compressive or tensile axial
stresses along energy piles, the magnitude of which increases with higher restrictions such as
structural load on top or higher toe resistance. Moreover, lower change in shaft resistance is
observed with increasing restrictions along the energy piles. In addition to the design,
deployment, and execution of the field test, a thermo-mechanical cyclic numerical model was
developed as a part of this research. In this numerical model, load-transfer approach was
coupled with the Masing's Rule in order to simulate the two-way cyclic axial displacement of
energy piles during temperature changes. The numerical model was validated using the field
test results for cyclic thermal load and thermo-mechanical load applications. It is concluded
that the use of load-transfer approach coupled with the Masing's Rule is capable of
simulating the cyclic thermo-mechanical behavior of energy piles.<br>Ph. D.
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Lam, Carlos. "Properties and applications of polymer support fluids in geotechnical engineering." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:ba0867c6-eb42-4b9a-a400-b464749855c5.
Full textAbstract:
Synthetic polymer fluids have been used as an alternative to conventional bentonite slurries for the excavation of foundation elements over the last two decades. Thus far their use has excited polarised views in the industry – some construction professionals avoid using them after hearing ‘horror stories’ about past failures whereas others believe that they are the future of support fluids because of the many benefits that they can offer. This situation has been found to be mainly due to a lack of understanding of what polymers really are and their properties. To address this issue, the various polymer products currently available in the market have been categorised based on their intended functions, and the fundamental properties of some of them have been characterised. The research showed that significant difference exists between polymers even of the same chemical family. Based on a series of rheological experiments, it was found that the properties of polymer fluids are highly dependent on the governing shear rate, time, and a range of site dependent factors. The research also showed that the current procedure for the interpretation of viscosity data is incorrect. After an analysis of the properties of currently available polymers, the latter part of the thesis describes a field trial carried out at a site in Stratford, East London. The aims of the trial were twofold: to compare the performance between piles constructed using bentonite and polymer fluids, and to assess the effect of extended pile bore open time for pile bores supported by polymers. From the results, it was found that the polymer piles showed much stiffer load–settlement response than the bentonite pile, and that a pile bore open time of up to 26 h had no adverse effect on the pile performance. The load test results have been carefully back-analysed using a range of methods. It was found that, compared to their bentonite counterparts, polymer fluids can improve the interface shearing resistance with Thanet Sand and the shear modulus of the Lambeth clay.
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Lusvardi, Cameron Mark. "Blast-Induced Liquefaction and Downdrag Development on a Micropile Foundation." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8747.
Full textAbstract:
Frequently, deep foundations extend through potentially liquefiable soils. When liquefaction occurs in cohesionless soils surrounding a deep foundation, the skin-friction in the liquefied layer is compromised. After cyclical forces suspend and pore pressures dissipate, effective stress rebuilds and the liquefied soil consolidates. When the settlement of the soil exceeds the downward movement of the foundation, downdrag develops. To investigate the loss and redevelopment of skin-friction, strain was measured on an instrumented micropile during a blast-induced liquefaction test in Mirabello, Italy. The soil profile where the micropile was installed consisted of clay to a depth of 6m underlain by a medium to dense sand. The 25cm diameter steel reinforced concrete micropile was bored to a depth of 17m. Pore pressure transducers were placed around the pile at various depths to observe excess pore pressure generation and dissipation. Soil strain was monitored with profilometers in a linear arrangement from the center of the 10m diameter ring of buried explosives out to a 12m radius. Immediately following the blast, liquefaction developed between 6m and 12m below ground. The liquefied layer settled 14cm (~2.4% volumetric strain) while the pile toe settled 1.24cm under elastic displacement. The static neutral plane in the pile occurred at a depth of 12m. From 6m to 12m below ground, the incremental skin-friction was 50% compared to pre-liquefaction measurements. The decrease in residual skin-friction is consistent with measurements observed by Dr. Kyle Rollins from previous full-scale tests in Vancouver, BC, Canada, Christchurch, New Zealand, and Turrel, Arkansas.
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Strand, Spencer R. "Liquefaction Mitigation Using Vertical Composite Drains and Liquefaction Induced Downdrag on Piles: Implications for Deep Foundation Design." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2330.pdf.
Full text
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Sanchez, Loana Henriquez. "Avaliação de soluções alternativas para o aumento de capacidade de carga de fundações por estacas helicoidais." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18132/tde-04122014-094332/.
Full textAbstract:
A utilização de estacas helicoidais como fundação de linhas de transmissão de energia elétrica tem aumentando significativamente no Brasil. No entanto, em alguns casos de obra, a camada de solo adequada para se instalarem as hélices da estaca encontra-se em profundidade economicamente inviável para o uso deste tipo de fundação. Esta foi a razão que motivou a presente pesquisa, que tem como objetivo avaliar soluções para a instalação de estacas helicoidais mais curtas, ancoradas em solo de capacidade inferior à necessária para atender às cargas de projeto. Nesta dissertação, foram avaliadas duas soluções alternativas para o aumento de capacidade de carga de fundações por estacas helicoidais, para os casos de carregamento de tração e compressão. A primeira alternativa verificada foi a injeção de calda de cimento em torno das hélices da ponta da estaca. A segunda solução testada foi o preenchimento com argamassa em torno da haste da estaca acima das hélices. Foram realizadas na presente pesquisa nove provas de carga (cinco de tração e quatro de compressão): três em estacas helicoidais convencionais, quatro em estacas helicoidais com injeção de calda de cimento e duas em estacas helicoidais com fuste de argamassa. Após a realização de provas de carga nas estacas, estas foram exumadas para se verificar a forma da coluna de argamassa e as formas de bulbos resultantes das injeções realizadas com calda de cimento. A partir dos resultados dos ensaios, foi verificado que a capacidade de carga da estaca á tração pode ser aumentada usando-se as alternativas testadas. Porém, são necessários mais ensaios para avaliar a eficiência destes procedimentos em diferentes condições de solo e configuração de estacas.<br>The use of helical piles as foundation for transmission lines has increased significantly in Brazil. However, in some sites, the soil layer suitable for installing the pile helices are considerably deep and it is economically unviable to use this type of foundation. This reason motivated the current study, which aims to evaluate solutions for the installation of helical piles anchored in soil with low capacity. In this research, it was evaluated two alternative solutions to improve the helical pile capacity. The first alternative is injecting a water/ cement mixture which is delivered to the ground throught holes, placed between the upper and bottom helices. The second alternative solution is helical piles with a mortar shaft. Nine pile load tests were performed for the present investigation (five in tension and four in compression): three on conventional helical piles, four on helical piles with injection, and two on helical piles with mortar shaft. After that, the helical piles were exhumed for the verification of the shaft shape and the forms of the bulbs resulting from injections performed with cement mixture. The results of these tests indicated that the uplift capacity of helical piles can be increased by using the alternatives tested. However, more tests are needed to evaluate the effectiveness of these procedures, in different soil conditions and pile configurations.
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Changchien, Chao Cheng, and 張簡昭澄. "Selection in Pile Foundation and Well Foundation." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/s3t824.
Full textAbstract:
碩士<br>國立臺北科技大學<br>土木與防災研究所<br>101<br>In C903 of Freeway NO.1 widening project Wugu-Yangmei section， the bridges were constructed along the hillside. It will take several months to excavate and retain by traditional procedure. The working place between the Freeway NO.1 and Ta-Ke-Keng Stream is very narrow， and the hillside along the freeway is on steep slope. The feasibility analysis of selection from pile foundation of original design changing to well foundation is needed.
When well foundation is constructed， the excavation area is small， the building equipment is small， and it has well efficiency. It is suitable for bridge foundation along hillside. These two foundations will be compared and evaluated from construction， environmental protection， shorten construction period， and landscape maintenance