Study On Seismic Performance Of Beam Bridge Based On Fuzzy Comprehensive Evaluation

The influence factors of the seismic performance of the bridge are complex.These factors are often difficult to accurately determined and the influence degree of single factor also has certain fuzziness.Therefore,the seismic performance of the bridge is often difficult to accurately evaluate.Based on the fuzzy comprehensive evaluation method,this paper chooses 3factors set,such as seismic wave,bridge structure,site condition as the evaluation index.In accordance with the “Regulations for the implementation of the seismic design of highway bridges” in the two level design,the provisions of the two stage design.The comment sets is divided into 5 levels,including excellent,preferably,commonly,poor and poor.And the weight of each factor is determined by the analytic hierarchy process.The membership functions are determined by the combination of Delphi method and distribution method.So a two stage fuzzy comprehensive evaluation model for the seismic performance of the general beam bridge is established.Finally,according to the principle of maximum membership degree to determine the evaluation results,so as to draw the general seismic performance of beam bridge structure fuzzy comprehensive evaluation method.In addition,the fuzzy comprehensive evaluation process is illustrated by the example of the Shoujiang bridge,which was suffered severe damage in Wenchuan earthquake.It proves the practicability and feasibility of using the fuzzy comprehensive evaluation method to study the seismic performance of the bridge.In this paper,we choose a continuous rigid bridge in Beijing as the engineering example to evaluate the seismic performance.Then we change the direction of earthquake action,the peak acceleration of earthquake,the site type respectively,so as to compare changes of the seismic performance analysis.Finally,the finite element model of the bridge is established by SAP 2000 to analyze the seismic performance of the bridge.Comparing it with the results of fuzzy comprehensive evaluation,it is further verified the practicability and feasibility of the fuzzy comprehensive evaluation method in the seismic performance evaluation of the general beam bridge.It can be used as reference for research,design and construction of seismic performance of general beam bridge engineering.