Analysis On Seismic Fragility And Economic For Typical Frame-Shear Wall Structure Based On The IDA Method

“Performance-Based Earthquake Engineering (PBEE)” has been attracted muchattentions from researchers recently. In terms of the achievements of PBEE in China, ithad made great developments. But there were still some problem which should benoticed, for example, it was not formed a uniform method for the predictions for thedamage of the structures in earthquake, and moreover there were different methods forthe predictions which estimated the same type of structure. It was focused on the“PBEE” evaluations of five typical frame-wall models which were simulated for thevarious of the rigidity characteristics with the fiber section model in PERFORM-3D,and it was discussed on seismic hazard analysis, dynamic response of structure, seismicfragility analysis and seismic economic loss analysis in this paper. Based on the study,some conclusions were achieved as follow:（1）Seismic hazard analysis for sttucture with different characteristic value of rigidityis based on the theory of extreme statistics,and seismic hazard curves of S a (T Y，5%)foreach structure indicated that as the characteristic value of rigidity decreased, thestiffness and the seismic action which was under the same exceeding frequency wasgradually increased, but the period was decreased gradually. In addition, with theincrease of the ground motion intensity, the exceeding frequency was gradually reduced,so that the results from increment dynamic analysis on basis of seismic hazard analysiswas reasonable.（2）In this paper,incremental dynamic analysis was used to structure analysis forstructures with different characteristic value of rigidity. S a TY,5%is the intensitymeasure and maxis the damage measure for incremental dynamic analysis.IDAcurvesis obtained through the structure analysis.With the increase of the characteristic valueof rigidity, the seismic performance of the structure increased either, in addition,decrease of characteristic value of rigidity improve the anti collapse capability ofstructure.（3）Seismic fragility analysis based on incremental dynamic analysis is the focus ofthis article. Firstly, Through K-S test we can prove that drifts obtained throughincremental dynamic analysis keep the lognormal distribution. Then, through lognormaldistribution function, find the exceeding probability of each structure, draw the curvesof damage analysis(exceedance probability-S a TY,5%). exceedance probability under different limit state of the structure shows that:when the characteristic value of rigidityis small,the damage of structure is small either,and the state of each structure is “inreasonable condition”or “slight damage”.With the increase of characteristic value ofrigidity,the damage of each structure became biger and biger.The probability at“moderate damage”and “serious damage”increased.（4）Total loss ratio curves for structures, which are drawn with total loss ratio forcharacteristic value of structural stiffness as ordinate and annual mean exceedanceprobability as abscissa, are derived from seismic fragility analysis curves. The total lossratio curve shows the variation law of the total loss ratio when the annual meanexceedance probability increases. Total loss ratios for every structure shows that thetotal loss ratio decreases with the increase of annual mean exceedance probability,among which the amplitude of decrease of the total loss ratio is much smaller at λ=7.3and λ=5.5. Then, the expected annual mean loss results from the integration of the totalloss ratio and the same method is used to get annual mortality rate and annual injuryrate. Till then, Four index are obtained through“Performance-Based earthquakeengineering”, which are expected annual mean loss, annual mortality rate, annual injuryrate and collapse margin ratio. In the end, decision-making advice is given according toone objective function and two constraint conditions. Objective function is economicloss at rear earthquake. One of constraint condition is the safety and the other is casualty.In this paper,the five typical frame-shear wall structures with=3.1~7.3showsthat,when satisfying two constraints and weight coefficient a=0.3， b=0.7, the optimalscheme is the structure with=3.1. In this case, Decision maker prefer loss of buildingin the period of use.when satisfying two constraints and weight coefficient a=0.7，b=0.3the optimal scheme is the structure with=7.3. In this case, Decision makerprefer cost of building in the period of use.