Reliability of Ductile Systems With Random Strengths

Abstract

A technique is proposed for determining the reliability of redundant ductile framed structures. A nonlinear structural analysis program and incremental load procedure are used to find the limit state function in load space for fixed structural properties. The failure probability of this deterministic structure is then computed by integrating the joint distribution function of loads over the failure region in load space. The procedure is extended to include randomness in the strength of the structure by introducing a random resistance variable unique to each load path. The statistics of this variable can be found by relating magnitudes of the load vector to successive component failure. The load space formulation of system reliability appears applicable to realistic structures of reasonable complexity.