Study On Seismic Performance Evaluation Method Of Highway Bridges In Service Of Qilin Area

Highway bridges played an indelible contribution to our country in infrastructure construction,goods transportation and the development of the national economy.It is the lifeline engineering of highway traffic system.The transport will interrupt if the highway bridges had big damaged in earthquake and it will make the disaster rescue becomes more difficult and bring the huge loss of life property,and have a secondary disaster in severe case.So it is extremely important to make the seismic evaluation of highway bridges.We have a huge number highway bridges in our country and their built in different years.How to evaluate the seismic of these bridges in conveniently and effectively is a key problem which needed to solve urgently.To solve this problem,this paper takes highway bridges in Qilin highway of Shanxi province as research background,and refer to the seismic performance evaluation methods and the related research results at home and abroad,formulated a set of two levels of seismic performance evaluation system for highway bridges.At first,lots of factors are analyzed detailedly which include the relevant parameters of highway bridge and earthquake related parameters,the grade of earthquake hazard level,seismic retrofit,vulnerability and earthquake hazard are defined too,finally determined bridges seismic grade and work out a suit of simple and distinct seismic evaluate of ?level.Then the deterioration properties of the material are analyzed by using the mechanical model of the damaged concrete and the mechanical model of the corroded steel bar,the method of component capability requirement ratio considering the deterioration of material properties is proposed,and the?level evaluation of seismic performance of highway bridges are carry out by using component capacity demand ratio as an index.At last,two grade evaluation system of seismic performance of highway bridge are carried out according to the actual bridge,we can judge the seismic performance of highway bridges clearly through the evaluation results,provides some suggestions for the reasonable use of funds and personnel for bridge reinforcement,determines the weak seismic performance of the bridge structure,and puts forward the simple reinforcement measures.