海上打桩过程中桩周土体强度弱化的数值模拟

邵红杰; 刘润; 林敏博; 徐余

海上打桩过程中桩周土体强度弱化的数值模拟 English Version

1. 天津大学水利工程仿真与安全国家重点实验室，天津 300072；2. 天津市建筑设计院，天津 300074

基金项目: 国家自然科学基金面上项目（51279127）；教育部新世纪优秀人才支持计划项目（NCET-11-0370）；国家创新研究群体资助项目（51021004）

详细信息

作者简介:
邵红杰(1986- )，女，硕士研究生，研究方向为岩土工程。E-mail: shaohongjie1205@sina.com。

中图分类号: TU43.1
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出版历程
- 收稿日期: 2013-02-28
- 发布日期: 2013-07-18

Numerical simulation method for soil strength reduction during pile driving in offshore engineering

1. State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China; 2. Tianjin Architects Design Institute, Tianjin 300074, China

摘要

摘要: 海上施工条件复杂多变增加了打桩施工的难度和复杂性，常常导致拒锤、溜桩等事故的发生。因此进行桩的可打入性分析并预估锤击数具有重要的意义。在连续打桩过程中，由于锤击反复作用，桩侧土体受到严重扰动，土体强度弱化，桩侧摩阻力明显降低，使得桩在连续贯入过程中的锤击数低于预测得到的锤击数。针对连续贯入过程中桩侧土体的强度弱化现象，对比分析了目前应用较多的线性法、非线性法、指数法、应力历史法等4种经验公式方法，针对其无法考虑土性特征对桩侧土阻力衰减的影响，基于一维应力波动理论和桩-土相互作用模型，提出了采用恢复系数法结合GRLWEAP软件来估算打桩过程中的桩侧土阻力。通过实际工程的打桩分析，与实测数据进行了对比，验证了该方法的可靠性。
- 打桩分析 /
- 波动理论 /
- 土体强度弱化 /
- GRLWEAP /
- 数值模拟
Abstract: In offshore engineering, the diverse and complicated construction conditions make pile driving more complex and difficult, which usually leads to refusing hammer and pile run during piling projects. Hence, it is crucial to predict the drivability of piles and to estimate the hammer blow counts accurately. In the continuous pile driving, since the soil around the piles is remolded heavily, the soil strength reduction and the frictional resistance decrease obviously. The calculated blow counts are usually much more than the measured data for continuously piling procedure. Four kinds of methods which can consider the soil strength reduction during pile driving analysis are compared. The methods include the linear formula method, nonlinear formula method, exponent formula method and stress history method. Since they all can not consider the effect of soil properties on soil resistance surrounding piles, a novel method is proposed. Based on the one-dimensional stress wave theory and the pile-soil interaction model, the proposed method estimates the soil resistance using the GRLWEAP software by using different restitution factors in different soil layers. The proposed method is verified by comparing the calculated results with the in-situ records of a practical project.
- pile driving analysis /
- stress wave theory /
- soil strength reduction /
- GRLWEAP /
- numerical simulation

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参考文献(1)

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