Stochastic Analysis of Load Combination

Abstract

This paper reviews the methods for combining loads idealized as Poisson processes. Hasofer's method for combining a Poisson square wave load with a Poisson impulsive load is extended to the case of a combination of one square wave load with an arbitrary number of impulsive loads. The problem of considering the effects of dead load is addressed. Both the instantaneous and the largest value in structural life time statistics of a combination are determined. The following load combinations are considered in the applications: (1) dead and live load on floors; (2) dead and wind load; and (3) a combination involving four loads. As the percentage of dead load with respect to the sum of all load averages decreases, it is found that all fractiles of the largest value distribution increase, even considerably. Finally, a new combination rule for practical use is proposed.