Calculation of Failure Probability of Caisson Breakwater Considering Correlation between Variables

In the general stochastic space, an asymptotic approximation of failure probability with random variables is presented in this paper. The extended Hasofer-Lind method for reliability index, together with asymptotic approximations of failure probability with correlated variables, is used in the reliability analysis for anti-sliding and anti-overturning of a caisson breakwater. The probability of failure modes of breakwater are carried out for an existing caisson breakwater at Qinhuangdao, China, and the accuracy of calculation result are also validated by comparing with the Level III method. It is shown that the probability of failure calculated by assuming independence of variables is less than that considering correlation among variables.