Stochastic Combination of Load Effects

Abstract

The problem of evaluating the probability that a structure becomes unsafe under a combination of loads over a given time period is addressed. The loads and load effects are modeled as either pulse (static problem) or intermittent continuous (dynamic problem) processes. The load coincidence method is extended to problems with both nonlinear limit states and dynamic responses. Results are compared with other methods, namely, methods based on upcrossing rate, simpler combination rules and Monte Carlo simulation. It is found that the load coincidence method is a versatile method for load combination of many types. It generally gives conservative results with good accuracy.