Condition Assessment Of Concrete Cable-Stayed Bridge Based On Analytic Hierarchy Process

As the rapid development of long span cable-stayed bridges in the past decades, their operational performance should be influenced by overload or degeneration of the material. These problems include rust and rupture of the cable, crack on the beam or tower, delamination of the deck, and invalidation of the drainage system. The problems mentioned above may not influence the load capacity of the bridge, but influence the serviceability greatly. Long span bridges are very important to a nation's economy. The enormous investment and significance make them get more and more recognition. So the assessment of the bridge becomes more and more important. Based on it, the working condition can be determined to present a management decision for the bridge.AHP(Analytic Hierarchy Process) is adopted as the assessment method of concrete cable-stayed bridge in this thesis. The main contents are as follows:Firstly, the development of cable-stayed bridges and many defects existing on them are introduced, and some usual evaluation methods are summed up briefly.Secondly, AHP is introduced. And based on the Code for Maintenance of Highway Bridges and Culvers and the mechanical property of cable-stayed bridges, a hierarchy assessment model is established based on AHP. By consulting several bridge specialists, the weight of every index is determined. Then in compliance with the need for condition assessment, the statistical weight is analyzed properly.Thirdly, the condition level and grade code is established. According to the theory of Variable Weight Synthesizing, the bridge's whole grade can be calculated to determine its condition level. And also the degree of grey incidence of some index is calculated to supply some reference to concerned department.Finally, the calculation program is carried out. Then an example of one certain concrete cable-stayed bridge, Shaximiao Bridge, is set to testify the correctness and practicability of the program.The method presented in this thesis is feasible and proved reasonable through application to the real bridge.