A failure-path independent method for analysis of structural system reliability

In order to overcome the disadvantages of traditional system reliability methods in the identification of significant failure modes and calculation of joint failure probability, a failure-path independent method is presented for structural system reliability analysis by combining the elastic modulus reduction method and the stochastic finite element method (SFEM). The stochastic responses by the SFEM were employed to define the element bearing ratio and the reference EBR, based on which an efficient dynamic criterion was developed for identification of highly stressed elements. The stochastic elastic modulus reduction method was proposed for simulation of internal force redistribution and damage evolution based on the principle of deformation energy conservation. The significant failure modes of structural system were identified according to the elastic modulus of the highly stressed elements in the limit state, while structural system reliability was calculated based on the joint failure probability of multi-failure modes. Investigation demonstrated the advantages of the proposed method over the traditional system reliability methods and its high accuracy and efficiency.