Research And Application Of Fuzze Synthetic Evaluation In Health Diagnose For Arch Bridge

Because the bridge structures collapsing to fall with every kind of reasons and bridge deterioration with time and ever increasing traffic loads raise concerns about safety and durability of aging bridges, the health condition of a bridge structure have become the focus in the engineering field. A large proportion of bridges in china are Arch bridges, and the arch bridges' distributing are also wide. For assuring transportation safety, having the existing arch bridges to be used sufficiently, it is necessary to do proper reliability diagnose for the arch bridges. The reliability diagnose ,evaluation is both the preceding work and the key procedure of the maintenance and reinforcement of the existing arch bridges.Since the complexity for influencing factors of safety degree and the fuzzy of evaluating rules, Fuzzy comprehensive based on analytical hierarchy process (AHP) are used in arch bridge's evaluate。The classification for numerous factors of affecting arch bridge safety is carried out based on the fuzzy synthetic evaluation method. The fuzzy judgment for safety grade of each factor is carried out one layer by one layer, and then the final results of bridge safety judgment through the fuzzy synthetic evaluation method. And the whole safety condition of the arch bridge can be understood quickly and accurately, which can provide the basis on the prior reinforcement of the arch bridge.Comprehensive evaluation healthy is important in the researching of the existing arch bridges. The research can be given reference to the scientific management of the existing arch bridges, and it has broad future in practical engineering. The main contents in this thesis are as follows:1.The development of arch bridges are rebiewed. The status of research on assessment of existing bridge has been summarized and introduced;2.Introduced the arched bridge common diseases, and analyzes its reasons;3.Assemble to the sub-health research of mankind, the ideas of bridge sub-health are provided. The method of more grades comprehensive fuzzy comprehensive evaluation in arch bridges health are suggested after discussing theoretical factors.4.Expounded the basic principle of analytical hierarchy process and fuzzy comprehensive judgment.5.The thesis has set up the arch bridge health evaluation model of multilevel fuzzy synthetical evaluation based on analytical hierarchy process. It has described how to use the method to evaluate the arch bridge health. By analyzing the datum in existence and the interrelated criterion, the thesis has put forward the means that can confirm the grade vector of bottom indexes.6. Evaluate the reliability of a arch bridge based on the article theory.