The Dynamic Behaviour of Pile Foundations in Seismically Liquefiable Soils

The Dynamic Behaviour of Pile Foundations in Seismically Liquefiable Soils PDF Author: Rohollah Rostami
Publisher:
ISBN:
Category : Electronic books
Languages : en
Pages : 0

Book Description
This chapter presents a concise overview of the mechanics of failure, analysis and requalification procedures of pile foundations in liquefiable soils during earthquakes. The aim is to build a strong conceptual and technical interpretation in order to gain insight into the mechanisms governing the failure of structures in liquefaction and specify effective requalification techniques. In this regard, several most common failure mechanisms of piles during seismic liquefaction such as bending (flexural), buckling instability and dynamic failure of the pile are introduced. Furthermore, the dynamic response commentary is provided by critically reviewing experimental investigations carried out using a shaking table and centrifuge modelling procedures. The emphasis is placed on delineating the concept of seismic design loads and important aspects of the dynamic behaviour of piles in liquefiable soils. In this context, using Winkler foundation approach with the proposed p,Äìy curves and finite-element analyses in conjunction with numerical analysis methods, are outlined. Moreover, the feasibility of successful remediation techniques for earthquake resistance is briefly reviewed in light of the pile behaviour and failure. Finally, practical recommendations for achieving enhanced resistance of the seismic response of pile foundation in liquefiable soil are provided.

Design of Pile Foundations in Liquefiable Soils

Design of Pile Foundations in Liquefiable Soils PDF Author: Gopal Madabhushi
Publisher: World Scientific
ISBN: 1848163622
Category : Science
Languages : en
Pages : 232

Book Description
Pile foundations are the most common form of deep foundations that are used both onshore and offshore to transfer large superstructural loads into competent soil strata. This book provides many case histories of failure of pile foundations due to earthquake loading and soil liquefaction. Based on the observed case histories, the possible mechanisms of failure of the pile foundations are postulated. The book also deals with the additional loading attracted by piles in liquefiable soils due to lateral spreading of sloping ground. Recent research at Cambridge forms the backbone of this book with the design methodologies being developed directly based on quantified centrifuge test results and numerical analysis.The book provides designers and practicing civil engineers with a sound knowledge of pile behaviour in liquefiable soils and easy-to-use methods to design pile foundations in seismic regions. For graduate students and researchers, it brings together the latest research findings on pile foundations in a way that is relevant to geotechnical practice.

Single Piles in Liquefiable Ground

Single Piles in Liquefiable Ground PDF Author: Rui Wang
Publisher: Springer
ISBN: 3662496631
Category : Science
Languages : en
Pages : 131

Book Description
This thesis focuses on the seismic response of piles in liquefiable ground. It describes the design of a three-dimensional, unified plasticity model for large post-liquefaction shear deformation of sand, formulated and implemented for parallel computing. It also presents a three-dimensional, dynamic finite element analysis method for piles in liquefiable ground, developed on the basis of this model,. Employing a combination of case analysis, centrifuge shaking table experiments and numerical simulations using the proposed methods, it demonstrates the seismic response patterns of single piles in liquefiable ground. These include basic force-resistance mode, kinematic and inertial interaction coupling mechanism and major influence factors. It also discusses a beam on the nonlinear Winkler foundation (BNWF) solution and a modified neutral plane solution developed and validated using centrifuge experiments for piles in consolidating and reconsolidating ground. Lastly, it studies axial pile force and settlement during post-earthquake reconsolidation, showing pile axial force to be irrelevant in the reconsolidation process, while settlement is process dependent.

Dynamic Behaviour of Pile Foundations with Soil-pile Interaction

Dynamic Behaviour of Pile Foundations with Soil-pile Interaction PDF Author: Yingcai Han
Publisher:
ISBN:
Category : Piling (Civil engineering)
Languages : en
Pages : 426

Book Description


Analysis of Pile Foundations Subject to Static and Dynamic Loading

Analysis of Pile Foundations Subject to Static and Dynamic Loading PDF Author: Amir M. Kaynia
Publisher: CRC Press
ISBN: 1000398560
Category : Technology & Engineering
Languages : en
Pages : 366

Book Description
This book presents computational tools and design principles for piles used in a wide range of applications and for different loading conditions. The chapters provide a mixture of basic engineering solutions and latest research findings in a balanced manner. The chapters are written by world-renowned experts in the field. The materials are presented in a unified manner based on both simplified and rigorous numerical methods. The first four chapters present the basic elements and steps in analysis of piles under static and cyclic loading together with clear references to the appropriate design regulations in Eurocode 7 when relevant. The analysis techniques cover conventional code-based methods, solutions based on pile-soil interaction springs, and advanced 3D finite element methods. The applications range from conventional piles to large circular steel piles used as anchors or monopiles in offshore applications. Chapters 5 to 10 are devoted to dynamic and earthquake analyses and design. These chapters cover a range of solutions from dynamic pile-soil springs to elasto-dynamic solutions of large pile groups. Both linear and nonlinear soil behaviours are considered along with response due to dynamic loads and earthquake shaking including possible liquefaction. The book is unique in its unified treatment of the solutions used for static and dynamic analysis of piles with practical examples of application. The book is considered a valuable tool for practicing engineers, graduate students and researchers.

Numerical Study on the Seismic Behavior of Inclined Piles in Liquefiable Soils

Numerical Study on the Seismic Behavior of Inclined Piles in Liquefiable Soils PDF Author: Yu Wang
Publisher:
ISBN:
Category : Earthquake resistant design
Languages : en
Pages : 164

Book Description


Seismic Performance and Simulation of Pile Foundations in Liquefied and Laterally Spreading Ground

Seismic Performance and Simulation of Pile Foundations in Liquefied and Laterally Spreading Ground PDF Author: Ross W. Boulanger
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 344

Book Description
Proceedings of a workshop on Seismic Performance and Simulation of Pile Foundations in Liquefied and Laterally Spreading Ground, held in Davis, California, March 16-18, 2005. Sponsored by the Pacific Earthquake Engineering Research Center; University of California at Berkeley; Center for Urban Earthquake Engineering; Tokyo Institute of Technology; Geo-Institute of ASCE. This collection contains 25 papers that discuss physical measurements and observations from earthquake case histories, field tests in blast-liquefied ground, dynamic centrifuge model studies, and large-scale shaking table studies. Papers contain recent findings on fundamental soil-pile interaction mechanisms, numerical analysis methods, and reviews and evaluations of existing and emerging design methodologies. This proceeding provides comprehensive coverage of a major issue in earthquake engineering practice and hazard mitigation efforts.

Geohazards

Geohazards PDF Author: Madhavi Latha Gali
Publisher: Springer Nature
ISBN: 9811562334
Category : Science
Languages : en
Pages : 763

Book Description
This volume comprises select papers presented during the Indian Geotechnical Conference 2018. This volume discusses concepts of soil dynamics and studies related to earthquake geotechnical engineering, slope stability, and landslides. The papers presented in this volume analyze failures connected to geotechnical and geological origins to improve professional practice, codes of analysis and design. This volume will prove useful to researchers and practitioners alike.

ICE Manual of Geotechnical Engineering Volume 2

ICE Manual of Geotechnical Engineering Volume 2 PDF Author: Tim Chapman
Publisher: Emerald Group Publishing
ISBN: 0727766848
Category : Technology & Engineering
Languages : en
Pages : 953

Book Description
ICE Manual of Geotechnical Engineering, Second edition brings together an exceptional breadth of material to provide a definitive reference on geotechnical engineering solutions. Written and edited by leading specialists, each chapter provides contemporary guidance and best practice knowledge for civil and structural engineers in the field.

The Axial Behaviour of Piled Foundations in Liquefiable Soil

The Axial Behaviour of Piled Foundations in Liquefiable Soil PDF Author: Mark Stringer
Publisher:
ISBN:
Category :
Languages : en
Pages :

Book Description
Understanding the mechanisms by which any engineering structure resists load is an essential requirement for its consistent and reliable design. The axial resistance which can be mobilised by piled foundations in liquefiable soils when subjected to strong shaking remains highly uncertain, and a number of piled foundations have failed in strong earthquakes as recently as 2011 . The lack of visible foundation distress in many such cases indicates that failure can occur as a result of the loss of axial capacity during an earthquake, as opposed to the laterally-dominated failure modes which have been the focus of the research community for the last 20 to 30 years. In this thesis, a series of dynamic centrifuge experiments have been carried out to establish how the distribution of axial loads along the length of a pile changes during a strong earthquake. In each test, a 2 × 2 pile group was installed such that its tips were embedded in a dense sand layer which was overlain by liquefiable soil. The tests examine the effects arising from the hydraulic conductivity in the bearing layer, the influence of axial pile cap support and finally whether there are any differences in the behaviour of nominally jacked or bored piles under seismic loading. The pile cap has been shown to play a substantial role in supporting axial loads during strong shaking. In cases where the pile cap was unable to support axial load, the majority of the axial loading was carried as pile end bearing, with some shaft friction being mobilised in both the liquefiable and bearing soil layers as a result of relative lateral displacements between the soil and pile. However, where the pile cap is able to support axial loads, the settlement of the pile cap into the soil led to a dramatic transfer of axial load away from the piles and onto the pile cap. These results imply that where substantial excess pore pressures may be generated at the depth of the pile tip, then the pile caps must be able to support significant axial load. The increased effective stresses below the pile cap were responsible for the mobilisation of shaft friction on the section of pile within the liquefiable layer. However, these piles were unable to mobilise shaft friction in the bearing layer due to the reduced lateral loading on the piles. The axial behaviour of the piled foundations after the end of strong shaking is affected by the recovery of pile end bearing capacity and is therefore strongly dependent on the hydraulic conductivity of the bearing layer. The axial behaviour of nominally bored and jacked pile groups in liquefiable soil deposits are very different under seismic excitation, with the installation process of the latter substantially altering the soil conditions around the tips of the pile, such that in contrast to the bored pile groups, the jacked pile groups did not accumulate settlements until significantly after the strong shaking had commenced. These results imply that the method of installation is an important factor in the seismic response of a foundation, and may be more pronounced for real earthquakes where the number of strong shaking cycles may be more limited than those simulated in the experiments.