The Research On Elastic-Plastic Seismic Response Analysis Method Of Tall Building Structures And Its Application

Though there were few casualties, the economic losses caused were very enormous after the erthquake occurred in some developed countries in the 1990s. It made researchers realize that a life-safe building design had not already been a kind of perfect earthquake resistance thought. Under such a background, the scholars of the United States and Japan have proposed the philosophy of Performance-based Earthquake Engineering(PBEE) design, the basic thought of which is making the structure designed satisfied with the expected performance objects during the lifetime.There are two practical elastic-plastic analysis methods in performance-based seismic design: nonlinear static analysis (pushover) method and incremental dynamic analysis (IDA) method. The pushover method is studied extensively at home and abroad, while the incremental dynamic analysis method (IDA) is gradually drawing attention.The focus of the paper is IDA method, the main contents and outcomes are listed as follow:The basic theory and procedure of the pushover method are described in chapter two of the paper. The different lateral load patterns are presented and the methods of obtaining the target displacement are introduced. Then the pushover method is carried out to evaluate the seismic performance of two frame structures.One of the goals of the PBEE is producing the mean annual frequency (MAF) of exceedance for the limit-states.This can be easily accomplished with the summarized results of IDA. The basic principle,the parameters selection and the statistical methods of IDA curves for the IDA method are introduced in detail. The definition of the limit-states and the calculation principle of MAF are also introduced in detail. The calculation process of the IDA method through the responses of a 25-story hybird structure is realized and the values of the limit-states are obtained.The basic theory of fragility analysis are discribed in this paper.The calculation process of the fragility analysis is introduced and the problems of integration and fitting of the curve are also discussed. IDA method is applied to the seismic fragility analysis and the estimation of the limit-states.While combining the IDA's results with the seismic hazard curve ,we can obtain the MAFs ,then the seismic behavior of structures under a rare earthquake can be estimated. IDA is resourse-intensive.Then SPO2IDA is introduced ,a new software tool that is capable of practically instantaneously and accurately recreating the seismic behavior of oscillators with complex multi-linear backbones. Through a series of transformations and parameters input,we can obtain the IDA curves.Then the results can be used to evalute the seismic demand and the capacity of structures, the conversion process of the curves can be see from two frame structures in this paper.