动力基础的竖向振动分析

THE VERTICAL VIBRATION OF DYNAMICALLY LOADED FOUNDATION

遵循动力基础的半空间理论 ,推演出基础刚性压力分布、柔性压力分布和抛物线压力分布的基础质量 静弹簧刚度 定值共振阻尼形式的基础竖向运动方程 ,并指出基础压力分布对基础动力反应的影响显著 ,不容忽视。进而讨论地基阻尼参数取值问题和动力反应实用计算方法。同时 ,在分析地基动力参数若干量测方法的基础上 ,论证模型试验方法与半空间理论的关系 。

A vertical vibration equation is deduced out with a constant mass?spring?damping model in the paper. It is based on the elastic half space theory for a dynamic machine foundation. It is recognized that there are three kinds of the pressure distribution under foundation: the rigid, flexible, and parabolic. It is observed that the dynamic response of a foundation is remarkably related to the pressure distribution. It is noted that to select the damping parameters and to establish a practical foundation design method are discussed. Moreover, the relationship between the modal test methods and the half?space theory are argued. At last, some helpful conclusions are obtained. Such as the statistical rules can be obtained when using the multiple curves method.