To appropriately perform designing of a conveyance device, setting of use conditions, etc., by determining the quantity of impact load caused by a collision of conveyed loose bulk material and thereby accurately finding the distributed state of impact load at a collided part when designing the conveyance device such as a belt conveyer.

A three-dimensional behavior analysis model M1 is prepared wherein the conveyed material is simulated by particles 'ptcl' while a conveyer belt 'B1', a feeder belt 'B2', etc., are simulated by flat plate members 'w, all'. The behavior of the particles 'ptcl' conveyed by the feeder belt 'B2' and falling from a receiving chute 9 onto the conveyer belt 'B1' is sequentially described by an individual element method (a behavior analysis step). The distributed state of impact load on cross rails 22 is computed (a load computation step) based on the behavior found in the behavior analysis step. By using the distribution of the impact load as input conditions, stresses, strains, displacement, and the like of the cross rails 22 are analyzed by the application of a dynamic finite element method (a stress analysis step).