非线性粘弹性土中单桩沉降时间效应分析新方法（英文）  

A new approach for time effect analysis in the settlement of single pile in nonlinear viscoelastic soil deposits

作　　者：Zhen-ya LI Kui-hua WANG Shu-hui LV Wen-bing WU 

机构地区：[1]MOE Key Laboratory of Soils and Geoenvironmental Engineering, Zhejiang University [2]Research Center of Coastal Urban Geotechnical Engineering, Zhejiang University [3]Engineering Faculty, China University of Geosciences

出　　处：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》2015年第8期630-643,共14页浙江大学学报（英文版）A辑（应用物理与工程）

基　　金：Project supported by the National Natural Science Foundation of China(Nos.51378464 and 51309207)

摘　　要：目的:提出一种新的简便方法,计算非线性土中单桩沉降的时间效应以及沉降稳定之后桩身侧摩阻力和桩身轴力的分布情况,为桩基础的设计提供参考。创新点:1.考虑土体的非线性(包括桩侧土和桩端土),计算结果更接近实际情况;2.采用基于行波分解的波动分析程序,计算桩身任意位置处的沉降,并据此计算任意位置处的侧摩阻力和桩身轴力;3.该方法既可以用于分析单桩沉降的时间效应,也可以计算不同加载等级下桩的最终沉降量,为设计提供参考。方法:1.采用线性阻尼器模拟土体的粘性,双曲线模型和理想弹塑性模型分别模拟桩侧土和桩端土的非线性,采用基于行波分解的波动分析程序得到桩身不同位置处的沉降、侧摩阻力及轴力计算公式(式(15)、(25)、(31)、(33)、(35)和(36));2.分析在不同桩土参数情况下,桩顶沉降随时间的变化规律(图6、8、10和12)及桩身侧摩阻力和桩身轴力分布情况(图7、9、11和13);3.将计算结果与工程实测结果进行对比,以验证理论模型的可行性(图14和15)。结论:1.单桩沉降的时间效应非常显著,并受到桩土参数的影响;2.本文提出的方法能够较准确地模拟工程实际情况。A new and simple approach is presented to analyze the time effect in the settlement of single pile and the distribu- tions of pile shaft resistance and pile axial force. First, the viscosity of soil is considered by using a linear damper, and the non- linear elasticity of pile lateral soil and pile end soil are simulated by using a hyperbola model and idealized elastoplastic model, respectively. Then, the settlement of the pile head, shaft resistance, and axial force along the pile are derived by virtue of a wave equation analysis program based on traveling wave decomposition. Based on the solutions, a parametric study has been under- taken to investigate the influences of the parameters of a pile-soil system on the settlement behavior of a single pile. Finally, the calculated results are compared with the measured results to demonstrate the effectiveness and accuracy of the proposed ap- proach. Note that the presented solution allows for a good prediction of the settlement behavior of a single pile and can provide a reference for the preliminary design of a pile foundation.

关 键 词：沉降 时间效应 双曲线模型 理想弹塑性模型 波动分析程序 

分 类 号：TU473.1[建筑科学—结构工程]