Abstract: Based on the modified first order second moment method (MFOSM) of structural reliability, an explicit iteration algorithm is proposed, which can avoid solving struatural per-formance function to get reliability index β and is very conven-ient for computer programme. An approximate method resolv-ing the problem that non-normal random variables can not be equivalent to normal distribution is also put forward. Then how to use the explicit iteration algorithm and general finite element method(FEM) software to calculate reliability is demonstrated, in which the effect of some random factors such as ma- terial, dimensions, loads, etc, can be logically considered and prob-ability finite element method(PFEM) is unnecessary. The valid-ity of the explicit iteration algorithm is illustrated through three examples finally.

Key words: Explicit iteration, Finite element method, First order second moment, Mechanology, Performance function, Reliability