The damage states are described in detail in terms of structural members and the relationship between the damage degree and the four types of performance limit states is built . the concept of the structural performance safety index is put forward and its calculation method is derived based on the structural deformation limit state equation . the deformation control design method is studied 从结构在地震作用下的破坏程度为出发点，对结构的破坏状态进行了描述，并建立了结构的破坏程度与结构四种性能极限状态之间的关系；提出了结构性能安全指数的概念，并以结构的变形极限状态方程为基础得到了结构设计性能安全指数的计算方法和结构性能等级的划分标准。
