Study On Failure Risk Assessment Of Local Members Of Prestress Concrete Cable Stayed Bridge

Bridge engineering is usually high investment,involving a wide range,long service life,once the bridge accident,the consequences are often very serious.A large number of cable-stayed bridges have been built in our country,such as the SanShui bridge of FoShan City Guangdong and the YangPu bridge of ShangHai and the QueShi bridge of ShanTou and the YongHe bridge of TianJin.With the increase of service life of cable-stayed bridge,most of the cable-stayed bridges have different degrees of damage.From the actual situation of the existing cable-stayed bridge operation observation,a lot of cable-stayed bridges have been failure.such as Stay cable lose effectiveness,Such examples could be multiplied indefinitely.The stress system of cable-stayed bridge is complex,each component is closely linked,if a key component failure will affect other components.It is of great significance to ensure the safety of the bridge that based on the study of failure risk of local members of cable stayed bridge,screening the risk factors that may cause the failure of local components.This paper is based on the main bridge of Foshan Sanshui bridge in Guangdong,study the?probability and loss of the bridge in the operation stage of cable lose effectiveness and Tension compression abutment lose effectiveness.Combined with field testing and parameter analysis and Bridge Risk Assessment Theory to obtained the list of risk factors of lead to cable lose effectiveness and Tension compression abutment lose effectiveness.And use fuzzy comprehensive evaluation method to evaluate the failure risk of the local members of the bridge.The main contents of this paper are as follows:First,Parameter analysis of bridge structure by establishing the finite element model of the main bridge of Sanshui Bridge,Sorting out the factors that may lead to bridge accidents,and as the basis for subsequent risk identification.Identify possible risk incidents,and calculate the effects of various hazards by parameter analysis.Identify various risk factors that may cause an accident,on the basis of the identification of various risk factors,analyze and screen the main risk factors,and induction the risk list.Secondly,calculate the relative weight of each factor by the analytic hierarchy process chalk up the ranking results of risk factors of cause cable lose effectiveness and Tension compression abutment lose effectiveness.Use the comprehensive evaluation method to evaluate the failure risk of local members of the bridge.Last,according to the evaluation results to make decisions,if the risk level is very low,accept the risk,if the risk level is high,issued by the corresponding risk control measures.