Cable-Stayed Bridge Duribility Evaluation Based On Fuzzy Comprehensive Method

Evaluation for bridge structural durability can not only assess the durability of the remaining life of the existing bridges, but also supply reference for the design of new bridge projects. Based on the study of domestic and foreign bridge in durability evaluation, a set of cable-stayed bridge durability state comprehensive assessment system was developed, using analytic hierachy process, variable weights theroy and fuzzy comprehensive evaluation method.The bridge structure is a complex system, and the factors affecting the durability state are complex and various, while the bridge durability condition assessment are always ignored. Analytic Hierarchy Process (AHP) make complex system hierarchical and simplification , and we get the initial assessment indexes weights through comparing the importance of each affecting factor. According to initial weights of evaluation index system and evaluation value, the variable weight of assessment indices were determined by variable weights principle. Fuzzy comprehensive evaluation method of bridge structure is a good way to solve the contradiction between the fuzziness of the bridge and the certainty of the arithmetic. Based on the analytic hierarchy process (AHP), combining cable-stayed bridge structure characteristics and according to relevant specification, it established cable-stayed bridge durability condition assessment recursive hierarchical model. According to the related standard, this paper establish fuzzy classification standard, membership functions and subordinate function hierarchical graph of the cable-stayed bridge's durability evaluation index.It established Hongdao Bridge durability condition assessment recursive hierarchical model and Hongdao Bridge durability state fuzzy classification standard, regarding Hongdao Bridge as engineering background. It classify the durability evaluation index of the Hongdao Bridge and test the standardized treatment model of the evaluation index with an example. This paper give the comparative judgment matrix of evaluation index in different level, and get the initial evaluation indexes weights of all levels, throughing programming and calculation. It verify the reliability of the durability evaluation system builded by this paper, through taking the durability condition assessment of Badong Changjiang Bridge Stay cabls system.