INTERVAL FACTOR METHOD FOR FEM ANALYSIS OF TRUSSES WITH INTERVAL PARAMETERS

A finite element analysis method for truss structures with interval parameters under interval applied forces is investigated in this paper. By using interval factor method, the structural physical parameters and geometric dimensions can all be expressed as the products of two parts corresponding to the interval factors and the deterministic value. The structural displacement and stress response can be expressed as the functions of the interval factors. The computational expressions for the lower, upper bonds and mean value of structural displacement and stress response are developed using the interval operations. By an example, the effects of the uncertainty of the structural parameters and loads on the uncertainty of the structural static response were analyzed, and the model and the method presented in this paper are verified. The main advantage of the method is that the effect of uncertainty of any individual structural parameters on the structural static responses can be reflected.