Analysis of Time-dependent Reliability of Concrete Gravity Dam Damage Based on Gray Theory

This paper applies the reliability theory, carries out time-dependent reliability over concrete gravity dam based on gray theory and damage theory, and applies the theory to practical engineering. Specific work are: 1. Apply the gray theory, build the GM model to analyze, supplement and predict the change and development laws of gravity dam random variables, and apply to structural reliability analysis for analysis of time-dependent reliability over the structure. 2. Adopt the damage mechanics theory, introduce the damage variable, build a new function based on four-parameter concrete model, reflect the concrete structure and the damage change features during the use, and thus analyze the structural time-dependent reliability at each period of time. 3. Carry out Taylor expansion to quadratic nonlinear term over the structural functional equation, combine with the engineering application principle, and obtain a feasible reliability utility computing method. This method does not need iteration, so it has greatly reduced the amount of computation, and has higher accuracy than the traditional first-order second-moment method.