A Simplified Finite-element Approach for the Analysis of Driven Piles

A Simplified Finite-element Approach for the Analysis of Driven Piles
Author: Toufic Elias Smayra
Publisher:
Total Pages: 180
Release: 1994
Genre: Finite element method
ISBN:

The analysis of axially-loaded driven piles is examined in this study using a finite-element model. The three-dimensional model accounts for the nonlinear behavior of the soil undergoing large deformation. The simulation of the penetration of the pile in the soil in the course of driving has been attempted in a previous study; the computational cost was however found excessive, thus, limiting the study to the driving of piles that are already in place (prebored piles). In this research, the penetration of the pile is simulated by gradually expanding a cavity in the soil in the form of the pile, until the desired depth of penetration is reached. The pile is then placed in the cavity to reach equilibrium. The driving of the pile is then continued using a nonlinear time-domain dynamic analysis in which the hammer blows are simulated by a periodic forcing function. A comparison is made between the response of actually (computationally) driven piles and piles driven by the expansion simulation. The response of prebored piles will also be compared with driven piles. The evolution of the state of stress and deformation in the soil and the soil resistance against the pile will be traced at all stages of the analysis.

Pile Behaviors in Shales Through Full-scale Static Load Testing, Dynamic Testing, and Finite Element Analysis

Pile Behaviors in Shales Through Full-scale Static Load Testing, Dynamic Testing, and Finite Element Analysis
Author: Md. Shafiqul Islam
Publisher:
Total Pages: 136
Release: 2021
Genre: Bridges
ISBN:

The design of driven piles has drawn significant interest among the researchers in soils, however occasionally addressed in the shale. A trustworthy design methodology for driven piles in shale is yet to be developed due to lacking a high-quality database. Consequently, the conventional static analysis methods developed for soils are used to estimate driven piles' resistances in shale, creating uncertainty in pile design. Moreover, the use of the Wave Equation Analysis Program (WEAP) for estimation of pile capacity is restricted by geomaterial input for shale. Additionally, the WEAP manual does not provide recommendations for the selection of dynamic properties for the analysis of piles. Also, the behavior of piles in shale, pile-shale interaction, and failure mechanism is unknown and yet to be established. Hence, this study aims to develop efficient static analysis methods for estimation of skin friction and end bearing of driven piles in the shale using 49 historical test piles data collected from the Kansas department of transportation (KDOT). Furthermore, the proposed static analysis methods are validated and compared against 23 dynamic test results of independent test pile data. This research recommends damping factors of 0.12 s/ft and 0.107 s/ft for two different input methods while keeping a toe and shaft quake value of 0.1 in for both methods. Moreover, the LRFD resistance factors are proposed for the developed static analysis methods and WEAP to achieve the target safety margin in the design and construction of piles in shale. Finally, using an extensive finite element analysis, the pile-IGM interaction behaviors and failure mechanism are investigated through validating the load-settlement response of the pile with static load test results.

Analysis of Pile Foundations Subject to Static and Dynamic Loading

Analysis of Pile Foundations Subject to Static and Dynamic Loading
Author: Amir M. Kaynia
Publisher: CRC Press
Total Pages: 401
Release: 2021-08-30
Genre: Technology & Engineering
ISBN: 1000398587

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.

Single Piles in Liquefiable Ground

Single Piles in Liquefiable Ground
Author: Rui Wang
Publisher: Springer
Total Pages: 131
Release: 2016-03-17
Genre: Science
ISBN: 3662496631

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.