中文摘要：

在《建筑抗震设计规范》（CB50011-2001）关于隔震结构的简化计算方法中，水平向减震系数的表达式和定义有些不符，假定的隔震结构地震作用分布规律也与实际情况略有出入。本文基于水平向减震系数的定义和实际隔震结构的地震作用分布规律提出了一种改进的隔震结构水平向减震系数、隔震结构总地震作用、隔震结构上部地震作用分布的计算方法，并提出了总水平地震作用减震系数的新概念。本文提出的改进方法具有表达准确、物理意义明确的特点。将本文提出的改进算法计算结果与时程分析计算结果比较，结果显示，改进方法的计算结果与时程分析结果接近，且分布规律一致。

英文摘要：

In the ＂Code for seismic design of buildings＂ , the expression of the damping coefficient in horizontal direction is not agreeable to its definition and the specified distributive form of seismic action of base isolation buildings is incongruent with the practical situation. Based on the definition of the damping coefficient in horizontal direction and the practical distributive form of the seismic action of base isolated structure, an improved simplified method of calculating the damping coefficient in horizontal direction, the total earthquake action and the earthquake action distribution of base isolation building is performed in this paper. A new concept of damping coefficient of total earthquake action is also presented. The formula expressions in this improved method are exact and their physical significance is definite. The time history analysis results for the two examples of base isolation building are compared with those computed by the improved method. It is showed that these two results are coincident, which have the same distributive form.