Prestressed Concrete Beam Bridge Structure Dynamic Endurance Assessment

As the rapid development of macroeconomic construction in china, the construction of transportation infrastructural facilities has been developed rapidly. The PRC(Prestressed concrete)beam bridge as an important component of the highway, it's durable reliability plays a significant role in indemnifying the highway's Normal use, safe traffic, playing the lurking traffic capacity and improving the operational effectiveness of the highway. Nevertheless, the problem of the PRC beam bridge's durability hasn't been paid enough attention for a long time. In addition, the multi-factors of exploration, design and construction during the serving. A number of concrete structures has appeared varying degrees disease in succession. It has affected the structure's normal use, and brought safe traffic operational problems.Based on domestic and foreign research achievements previously, for researching the important topic of duiability assessment of the PRC beam-bridge structure, the probability theory, the concrete structures theory, the fuzzy mathematics theory, the electrochemical theory, the tructural reliability theory, and the detection techniques are employed comprehensively in this thesis. The main issues and results are as follows:(1) The current domestic and foreign research achievements are systematic elaborated, the existed issues in the research have been pointed out.(2) Combinated the characteristics of a large number of small and medium-sized span concrete beam-bridge in Henan, the characteristics beam-bridge diseases have been summarized, its means of classification has been drawn up, and the the beam-bridge related detection techniques of durability has been introduced.(3) Based on the disease findings of beam-bridge in Henan, the basic corrosion mechanism of Henan's PRC beam-bridge has been researched, and the carbonation of concrete, the mechanism of chloride ion erosion and durability of concrete structures have been researched respectively.(4) The main factors of impact on the durability of PRC structures have been systemtic analyzed, the durability assessment system of PRC structures based on the theory of fuzzy comprehensive evaluation has been put forward. The used beam-bridge structure's durability multi-level fuzzy comprehensive evaluation based on detection has been achieved. Combined with the project examples, the feasibility of assessment method has been verified.(5) The failure durable criterion of PRC beam-bridge structure under the atmospheric environmen has been established. Combining with the project examples, through the Monte Carlo random simulation, the dynamic reliability anslysis of PRC structure based on concrete carbonation has been carried out.(6) Based on the given failure criterion, combined with the statistical analysis of the probability distribution characteristics of the structural durable factors under the chloride ion erosion environment, through the Monte Carlo random simulation, the dynamic reliability anslysis of PRC structure under the chloride ion erosion environment has been analyzed and researched. Combining with the project examples, the impact of structural durability on construction error has been researched.(7) The research work of this thesis has been summarized, and the research trends in the future are has been forecasted.