Determine the expectation, variance and reliability in some bending beams within their cracks and flexural stiffness EI (x) which is the stochastic parameter

This paper presents calculating the bending beams following the stochastic method. Under the finite element method, the structural model is established to determine the expectation, variance of node displacements, and then of inner forces. The structures have cracks, flexural stiffness EI (x) which is the stochastic parameter. The results of these models are the safe probability of the beams, will are applied to examine, explore the structures as on theory models as on reality models.