The Safety And Reliability Unde The Urltimate Limit State Study On RC Beam Bridge Component

With increases of material degradation and volume of traffic, the concrete beam bridge will present various damage. And it will influence the normal use of the bridge unavoidably. Therefore it's important to study on the safety and reliability assessment of concrete beam bridge. This text has studied concrete beam bridge component assessment method and standard of the safety and reliability under the ultimate limit state which had applicated the reliability theory. The main research contents are as follows:1) This paper have summarized and analyzed the current research of assessing method and standard of structure and have evaluated the method and standard in the existing structure.2) Based on analyzing the main influence factors of component resistance which is decaying in time and the time-dependent model of the factors. And the situation that the situation of the bending element under certainly damaging isn't satisfied the plane section assumption is considered. With the analysis of bending strength of cross section of the rectangle cross-section and single-reinforced beem as a example, the strength time-dependent model of members could be derived under the formula of concrete structural design code. With the rectangle cross-section and double-reinforced beem as a example, the strength time-dependent model of members could be derived from the destruction model of corrosion R.C. bending members.3) This paper Sum up and summarize the statistical parameter of resistance and loading effect and consider the influence of the factor of overloading etc. in the hope of getting the safety assessing method of the existing concrete beam bridge.4) Based on the principle of calibration, assessment standard of component under the ultimate limit state will be calculated with procedure of JC method which is Programmed with matlab.5) The Rationality of the assessing method and the standard is proved with project embodiment...