The reliability assessment of in-service bridge based on probabilistic and non-probabilistic hybrid reliability model

Due to the complexity of the existing bridges as well as the impact of the survey methods and funds, interval variables are the main parameters, there are few random variables and they are mostly of normal or lognormal distribution and are difficult to be solved with the conventional probabilistic and non-probabilistic hybrid model. Therefore, this paper presents a new probabilistic and non-probabilistic hybrid model. First, take a realized value for the interval variables, get the reliability indexes with the first-order second-moment center-point method, establish a second-order functional equation only containing the interval variables based on the provisions of the existing regulations on highway reliability and finally solve the non-probabilistic reliability indexes so as to evaluate the hybrid reliability of the existing bridges. Via example evaluation, the effectiveness of the method is verified.