均匀土-桩基-结构相互作用体系的计算分析

本文以结构－地基动力相互作用振动台模型试验为基础，结合通用有限元软件ANSYS，对均匀土－桩基－结构动力相互作用体系进行了三维有限元分析。计算中土体采用等效线性模型，利用面－面接触单元考虑土体与结构交界面的状态非线性，计算与试验得出的规律基本一致。桩基与土体间发生了脱开再闭合和滑移现象。桩身应变幅值分布呈桩顶大、桩尖小的倒三角分布，角桩的应变幅值较大，边排中桩和中桩的应变幅值较小。桩土接触压力幅值呈桩顶小、桩尖大的三角形分布。在沿振动方向的三排桩中，边排桩的滑移比中排桩的滑移量大。通过计算分析与试验的对照研究，验证了采用的计算模型与分析方法的合理性，为结构－地基相互作用的进一步研究奠定了基础。

Computational analysis of dynamic homogeneous soil-pile-structure interaction

Three dimensional finite element analysis of homogeneous soil pile structure shaking table test is carried out in this paper. General purpose finite element program ANSYS is adopted in the analysis. Commonly used equivalent linearity model is chosen to consider the non linearity of soil and the changing status non linearity of soil structure interface is considered by surface to surface contact element. Issues drawn from computational analysis are consistent with test results. The phenomena of separation, reclosing and sliding occur between pile foundation and soil. The distribution of the strain amplitude along the pile is the shape where the large strain is at the top of the pile and the small strain is at the tip of the pile. And the strain amplitude of pile at corners is bigger than middle pile of side row and center pile. The distribution of the contact pressure on the pile soil interface is in the shape where the small pressure is at the top and the large pressure is at the bottom. The pile's sliding of side row is bigger than that of middle row along the vibration direction. The rationality of computational model and analysis method is verified through comparison research between calculation and test results. The present work lays a foundation for further research on SSI.