Study On State Evaluation Of Long-Span Prestressed Concrete Cable-Stayed Bridge

Increasing traffic volume and harsh service environment pose a serious challenge to the durability and safety of long-span prestressed concrete cable-stayed bridges.It was of great engineering value to accurately grasp the health status of cable-stayed bridges.Therefore,different methods were adopted to study the state evaluation of long-span prestressed concrete cable-stayed bridge,including load experiment,etc.Main research work and conclusions were as follows:(1)Fuzzy comprehensive evaluation theory was studied from the aspects of representation method of fuzzy set,main operators,operation rules,etc.The membership function of evaluation method was determined.The maximum membership method was used to process evaluation vector,and the process of multi-level fuzzy comprehensive evaluation was proposed.(2)Five state levels of long-span PC cable-stayed bridge were determined.Service environment and mechanical characteristics was considered,the state evaluation model of long-span PC cable-stayed bridge was established.Corresponding relationship between the bottom index evaluation standard stated and the dimensionless score was established and the weight of stated evaluation index was determined by AHP method,and the evaluation criteria of each level index in long-span PC cable-stayed bridge state evaluation system were formulated.(3)Load tests and cable force tests were carried out on a long-span bridge,its’ length is473.5m.The results show that all components of the bridge were in normal working condition.Evaluation method established in this paper was used to evaluate working status of bridge,and it has achieved good results,which were in good agreement with the actual results.(4)The fuzzy comprehensive state evaluation system of long-span PC cable-stayed bridge was developed,which improves the state evaluation efficiency of long-span prestressed concrete cable-stayed bridge on the one hand,and provides reference for the development of the state evaluation system of bridges in China on the other hand.