Rc Bridge Life Reliability Analysis Method,

We have gained great achievement in the study of confidence level of engineering structure. However many RC bridges which were built before 1980 appear slump, because these bridges are not appraised reasonably in advanced. In the basis of confidence level's theory this paper puts forward a kind of analysis method of old bridges' reliability appraisement, service life and surplus service life. This will supply law of reinforcement and reformation for the old bridges near service life, and further makes the accident occurrence to lowest probability.This paper bases in the analysis of mechanical structure's reliability service life, and presents analysis method of confidence level of bridge structure's service life. The analysis uses the Monte-Caro and Response Surface method, builds the resistance model and load model of bridge structure, and in the ANSYS program's reliability module sets the variables of the based time's material nature and load character, at the same time appoints the distribute shape of every variable. By the program's calculation we can get the bridge's stress and deforming, leaning against two reliability determination criterions obtain the different confidence level in different time, draw the bridge's time-confidence level curve, and directly read the different time's confidence level from the curve. This paper only calculates the freely supported RC beam, in fact the method is fit for every RC bridge, but we must consider more time variables of all materials' common work in the course of building model.