Harichandran, R. S., and Chen, M.-T. (1996). "Statistical moments of principal stress-related quantities in random vibration analysis." Proceedings, 7th ASCE Specialty Conference on Probabilistic Mechanics and Structural Reliability, Worcester, Massachusetts, 962-965.

Abstract

Random vibration analysis is being used more widely in practice for a variety of engineering problems, largely due to the availability of such analysis capability within popular finite element software such as ANSYS, I-DEAS, NASTRAN, STARDYNE, etc. The computation of statistical moments of Cartesian stress and strain responses in this analysis is usually done through a modal summation approach or a direct transfer function approach (Harichandran and Ali 1995). For design applications quantities related to principal stresses or strains are usually of interest. However, the approaches used to compute Cartesian stresses and strains cannot be used to compute statistical moments of principal stresses or strains because the directions of these quantities are not fixed (i.e., in deterministic time history analysis, the directions of principal stresses and strains can vary at each instant of time). Use of the first-order second moment (FOSM) method to estimate moments of principal stress-related quantities is explored, and its accuracy is ascertained by comparison with Monte Carlo simulation results.