阶梯地形对西昌昔格达组三维地基地震动影响

为研究西昌昔格达组阶梯地形标高突变对地震动响应规律,选取攀钢西昌钒钛钢铁新基地地基工程为背景工程.以2个地基方案为研究对象,用有限元软件构建2个三维地基模型并模拟地震动作用下模型表面3个方向地震动加速度分布.通过分析得出如下结论:阶梯地形标高突变对水平方向加速度放大系数影响甚小,而竖直方向加速度放大系数骤增,但是否随着标高突变量增大而增大,有待进一步研究;从阶梯地形角点处向内侧延伸,竖直方向加速度放大系数又减小；竖直方向加速度放大系数随着输入地震动强度增大而减小；输入地震波强度越大,标高突变引起竖直方向加速度峰值增大越显著.

Seismic Response of Step Topography to Xigeda Formation of Xichang Three-dimensional Subgrade

In order to study the seismic response of Xichang Xigeda step terrain elevation mutation on the ground motion.Foundation engineering of the Panzhihua Vanadium and Titanium Steel new base in Xichang has been selected as background.Two Foundation programs were studied as the research objects,two three-dimensional foundation models built with finite element software simulated distribution in three directions of ground motion acceleration of model surface.Following conclusions have been concluded: terrain elevation step mutation has very small influence on the horizontal acceleration amplification coefficient but vertical acceleration amplification factor surge.Whether it increases with the increase of elevation mutation,further study is needed;From the ladder terrain extends to the inside corner point,the vertical acceleration amplification factor decreases;vertical acceleration amplification factor decreases with increase of ground motion intensity;the greater the intensity of seismic waves inputs the more significantly vertical acceleration caused by elevation mutations increases.