Evaluation And Reinforcement Of The Tied Arch Bridge Based On Reliability Study

Bridges are the hinges of traffic system, playing an important role in the national economic and society. Along with the extension of the bridge service life, international community increasingly pay attention to the safety of the existing bridge. Now the assessment of bridges is becoming a district which need to enhance urgently, so the reasonable evaluation on the safety of bridges is an urgent and important task.In this paper, a method of existing bridges evaluation and service life prediction based on time-dependent reliability analysis is presented. According to the structure weaken rule, we can forecast the service life of existing bridges. And proposed in this foundation, three kinds of bridge structure reinforcement plans based on time-dependent reliability analysis is presented, and the efficient appraisal to these three plans have carried on. The main achievements are briefly mentioned as follows:1. The static reliability method is always adopted in the reliability analysis of structure, and this method ignore the resistance reduction with time. To overcome the shortage ,in this paper, the time parameter "t" is introduced into the structural resistance and load model, and it makes the calculation of the dynamic reliability available.2. According to the weaken rule of bridges structure performance, forecast of the bridge structure residual life has carried on.3. Three kinds of bridge structure reinforcement plans based on time-dependent reliability analysis is presented, and the economical analysis to these methods has carried on to provide the powerful basis for the engineers and technicians decision-making to the bridge reinforcement.The assessment of bridges is a studying field which is more synthesis subject and correlate with many complicated theory, the researches are extremely difficult, but those applied prospect in engineering are vast, the theoretical worth is significant. There is a series of achievement in this dissertation, Along with the theory becoming more and more, this studying field will be developed in depth.