桩土动力分析中接触模型的研究

本文分析了目前常用ANSYS软件中土-结构动力作用中接触单元的工作机理,认为采用此软件中的接触单元对桩土动力接触分析会带来一定的误差。文中通过对桩-土-结构的动力相互作用简化分析中常用的Goodman接触单元的分析,在现有的Goodman单元的基础上加上阻尼成分,解决了Goodman单元只能考虑桩土之间力的传递,而不能考虑桩土动力相互作用中部分能量的耗散问题。通过分析比较,得出在中小地震作用下Goodman接触单元考虑阻尼后上部结构所受弯矩﹑剪力以及水平位移都有不同程度的降低。可见采用原来的Goodman单元分析高估了上部结构的受力和变形。

Studies on contact model of soil-pile dynamic interaction

The working mechanism of contact elements in ANSYS software, which would bring some errors to the results of soil—pile interaction, was analyzed. Through analyzing the Goodman element in the soil—pile—superstructure interaction, and modifying the Goodman element by adding the damping component, the problem that the Goodman element did not describe the energy dissipation during dynamic interaction was solved. The seismic response (moment, shear force, displacement, acceleration) of superstructure was reduced by use of the modified Goodman element under moderate earthquake.