STATISTICS OF THE VON-MISES STRESS-RESPONSE FOR STRUCTURES SUBJECTED TO RANDOM EXCITATIONS

Finite element-based random vibration analysis is increasingly used in computer aided engineering software for computing statistics: (e.g., root-mean-square value) of structural responses such as displacements, stresses and strains. However, these statistics can often be computed only for Cartesian responses. For the design of metal structures, a f ailure criterion based on an equivalent stress response, commonly know n as the von Mises stress, is more appropriate and often used. This pa per presents an approach for computing the statistics of the von Mises stress response for structures subjected to random excitations. Rando m vibration analysis is first performed to compute covariance matrices of Cartesian stress responses. Monte Carlo simulation is then used to perform scatter and failure analyses using the von Mises stress respo nse.