Vertical dynamic analysis of the pile in unsaturated soils based on COMSOL
YE Zi1,2,CHEN Yonghui1,2,KONG Gangqiang1,2,CHEN Geng1,2,XU Jie1,2,HU Nan1,2
1. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing 210098, China;
2. Suzhou Research Institute of Hohai University, Suzhou 215100, China
Abstract:The groundwater level determines that there is a large number of unsaturated soils on the soil surface, and its dynamic characteristics are significantly different from those of saturated medium or single-phase medium. As the main medium interacting with piles, unsaturated media have a critical effect on the dynamic behavior of piles. In this paper, considering the unsaturated characteristics of the soil around a dynamically loaded pile, based on the wave equation of the unsaturated poroelastic medium, the motion equation of the pile and the boundary condition, the Partial Differential Equation module in COMSOL Multiphysics software is used to establish a dynamic mathematical model of the interaction between the pile and the unsaturated soil with complex characteristics, such as stratification, transverse isotropy, inhomogeneity and so on. Meanwhile, several complex characteristics of soils and piles can also be reflected in this model. After verifying the correctness of the COMSOL model by comparing with the existing literature, a series of numerical examples were designed to discuss the influence of factors such as the soil saturation and inhomogeneity on the vertical dynamic impedance of a pile.
叶梓1,2,陈永辉1,2,孔纲强1,2,陈庚1,2,徐洁1,2,胡楠1,2. 基于COMSOL的非饱和土中单桩垂直动力特性研究[J]. 振动与冲击, 2024, 43(12): 46-52.
YE Zi1,2,CHEN Yonghui1,2,KONG Gangqiang1,2,CHEN Geng1,2,XU Jie1,2,HU Nan1,2. Vertical dynamic analysis of the pile in unsaturated soils based on COMSOL. JOURNAL OF VIBRATION AND SHOCK, 2024, 43(12): 46-52.
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