Full Text:   <1558>

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CLC number: TU413

On-line Access: 2020-03-17

Received: 2019-11-18

Revision Accepted: 2020-02-12

Crosschecked: 2020-02-26

Cited: 0

Clicked: 3169

Citations:  Bibtex RefMan EndNote GB/T7714

 ORCID:

Ling-gang Kong

https://orcid.org/0000-0002-5824-1275

Zhong-chang Zhang

https://orcid.org/0000-0001-8172-2221

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Journal of Zhejiang University SCIENCE A 2020 Vol.21 No.3 P.179-192

http://doi.org/10.1631/jzus.A1900590


Nonlinear analysis of pile groups subjected to combined lateral and torsional loading


Author(s):  Ling-gang Kong, Zhong-chang Zhang, Yun-min Chen

Affiliation(s):  Institute of Geotechnical Engineering, College of Architectural and Civil Engineering, Zhejiang University, Hangzhou 310058, China

Corresponding email(s):   klg@zju.edu.cn

Key Words:  Combined lateral and torsional loading, Pile groups, Twist center, p-multiplier, Group effect


Ling-gang Kong, Zhong-chang Zhang, Yun-min Chen. Nonlinear analysis of pile groups subjected to combined lateral and torsional loading[J]. Journal of Zhejiang University Science A, 2020, 21(3): 179-192.

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journal="Journal of Zhejiang University Science A",
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%A Ling-gang Kong
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%A Yun-min Chen
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A1 - Yun-min Chen
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DOI - 10.1631/jzus.A1900590


Abstract: 
An empirical approach has been developed to analyze the nonlinear response of a pile group with arbitrarily distributed piles subjected to combined lateral and torsional loading. In this approach, the concept of instantaneous twist center is applied to analyze the displacement relationship of pile heads and establish the static equilibrium equations of the pile cap. The horizontal interaction among the individual piles is considered through the generalized p-multiplier. The coupling effect of lateral resistance on the torsional resistance of each pile is quantified using an empirical factor β; the lateral and torsional nonlinear responses of individual piles are modeled by p-y and τ-θ curves, respectively. The proposed approach not only captures the most significant aspect of the group effect and coupling effect in a pile group subjected to combined lateral and torsional loading, but also automatically updates p-multipliers of individual piles based on pile cap displacements. The proposed approach was verified using results of model tests on pile groups subjected to lateral loading, torsional loading, and combined lateral and torsional loading, separately. In general, the pile cap response and the transfer of applied loads in the pile groups agree well with the test results.

This manuscript presents the development of an empirical approach to predict the nonlinear response of a pile group under eccentric lateral loading with a rigid pile cap. The model development is interesting. It seems the analytical results fit the experimental test results well. Its simplicity will allow for easy adoption by further study and by industry.

水平偏心受荷群桩的非线性分析

目的:群桩基础在近海建/构筑物及桥梁中广泛应用,而风、浪、船舶撞击等在群桩基础中产生的水平和扭转荷载往往影响群桩基础的安全. 本文旨在提出一套能够计算水平和扭转荷载联合作用下的群桩非线性响应简化分析方法.
创新点:1. 采用广义p乘子法考虑群桩中各桩水平变形导致的桩-土-桩相互作用; 2. 建立基于瞬时转动中心的基桩桩头位移关系和承台平衡方程.
方法:1. 通过理论分析给出基桩桩头位移之间的关系,建立承台平衡方程; 2. 采用荷载传递模型(p-yτ-θ曲线)模拟桩周土体非线性响应; 3. 采用广义p乘子法考虑群桩中各桩水平变形导致的桩-土-桩相互作用,并采用耦合因子计算基桩中推-扭耦合响应; 4. 通过迭代方法求解各基桩p乘子和群桩响应.
结论:1. 多组算例均表明本文提出的群桩非线性分析模拟能够较准确地模拟群桩响应,尤其在承台位移较大的情况下; 2. 广义p乘子能够有效地模拟群桩效应的主要部分; 3. 模型中的简化公式能够应用于实际工程问题分析.

关键词:水平和扭转组合荷载; 群桩; 转动中心; p乘子; 群桩效应

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article

Reference

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