Computer solution for the reliability index

A computer procedure to calculate the second moment reliability index for any linear or nonlinear failure condition has been developed and is presented in the form of a Fortran subroutine. The program calculates reliability index by an iterative numerical procedure and, in addition, provides information regarding the relationship between reliability index and failure probability to enable a suitable approximation to be chosen for the latter. An example is provided to illustrate the use of the program in computing a value for the reliability index and in carrying out a sensitivity analysis. Listings are provided of the reliability index subroutine together with ancillary programs employed in the illustrative example.