Reliability Analysis of a Truss Structure Considering Structural Damage and Spatial Correlation between Random Variables

Abstract

In this study, a reliability analysis is performed for a truss bridge considering uncertainties in structural properties and applied loads, structural damage, and spatial correlation between random variables. Two limit states are considered: a serviceability limit state based on allowable deflection and a stress limit state based on allowable stress. The Level II reliability analysis method, which is known as one of the moment methods, and the Level III method based on sampling techniques are used in the reliability analysis. In this study, the effects of structural damage and spatial correlation between random variables on the reliability index are intensively investigated. Results of the reliability analysis showed that structural damage has different effects on the reliability index and probability of failure in terms of the limit state and damaged member. With respect to spatial correlation, the probability of failure increases as the spatial correlation coefficient between random variables increases. Therefore, it can be concluded that structural damage and the spatial correlation between random variables should be reasonably considered to achieve a more rational reliability analysis.