The Reliability Comprehensive Evaluation And Optimum Selection Of Strengthening Schemes Researching Of The Existing Stone Arch Bridges

Lacks of carrying capability. material aging and damages in the existing bridges have been noticed all over the world. Relevantly servicing. evaluation and reconstruction for existing bridges have become the focus in the engineering fiel. dThe reliability evaluation is both the preceding work and the key procedure of the maintenance and reinforcement of the existing stone arch bridges. According to results of the comprehensive evaluation. it can be decided whether the structure needs maintenance and reinforcement or not. then select reasonable choice of reinforcement schemes in numerous schemes.Based on summarizing domestic and foreign results about the reliability comprehensive evaluation of existing bridges. more research on the comprehensive evaluation of concrete arch bridge has been accomplished in this thesis. The main contents in this thesis are as follows:1. The essence and character and the method of calculation of the evaluation about reliability of existing structure is expounded.2. The essence and character and the method of calculation of the comprehensive evaluation about carrying capacity reliability of existing stone arch bridges is researched. Many complicated factors which influence the effcet of the strengthening are analyzed and the two-level appraisal index system is established. The types and levels of the index are defined. Therefore proper assessment index can be chosen.3. The conventional methods of reinforcement including their ranges in point about above of arch bridge are analysed. Many complicated factors which influence the effect of the reinforcement and the basic principle of select optimum methods are analyzed. and the two-level multilevel fuzzy comprehensive decision system is established.4. Utilizing the results of comprehensive evaluation about reliability of stone arch bridge. Reasonable and scientific of the optimum methods and multilevel fuzzy decision system is substantiated.Results of research is substantiated. Using the theories of fuzzy appraisal and.fuzzy decision. mathematics model for the optimization of strengthening scheme is set up and applied to strengthening of used bridges. The difficulty of the determination of the weight of each factor can be overcome. Finally. the model is verified in a practical example of strengthening.