Safety Evaluation Of Bridge Based On Fuzzy-AHP

To prolong the bridge life and security bridges running normally, it is significant necessary to conduct safety inspection of the bridge regularly. Many methods of bridge safety inspection were presented, including qualitative analysis and quantitative analysis. As a common and single method of bridge evaluation, that the safety situation of bridge system is appraised systematically and comprehensively will be difficult, and therefore the integrated evaluation methods can perform quite well. Based on this, a FAHP-model combining analytic hierarchy process with fuzzy comprehensive evaluation is constructed, which can be applied to bridge safety evaluation. The evaluation system of bridge based on analytic hierarchy process makes bridge safety assessment more objective, scientific and effective. Judgement matrixes based on different scales are established, and the optimal scale is obtained according to consistency calculations of judgement matrixes. The evaluation index weight calculated based on the optimal scale is used as fuzzy weight sets. According to field detection on bridge safety condition and fuzzy sets, the mark of bridge safety status is determined, and then the situation level of bridge safety is obtained. The model for bridge safety evaluation is simple and practical, and it has been widely put into practice, detecting bridge diseases.in accordance with investigation of bridge appearance. The main conclusions about the research on bridge safety evaluation are the following several aspects.1. The primary causes for the aging and damage of bridge structural components were obtained through hazard identification of bridge disease, which included improper bridge design, man-made destruction, environment factors and natural disasters.2. The fuzzy analytic hierarchy model was built based on analytic hierarchy process(AHP) and comprehensive fuzzy evaluation. And the scale selection in AHP was explored, at the same time, the models and calculations of AHP and fuzzy comprehensive evaluation were studied.3. To prove the practicality of the method, the improved method is applied to an engineering example for safety detection of Shiqiao Bridge. Detecting the bridge disease and using the FAHP model, the score of the bridge safety condition is 75.48, and according to the evaluation set, the level of the bridge is 3-level. With serious problems existing in this practical example, and the corresponding measures were proposed, which can provide scientific reference for bridge safety management.