Abstract: Prefabricated steel bridge is a temporary or semi-permanent bridge structure. When the vehicles pass through the bridge, large internal force and deformation of the bridge structure will occur, and higher requirements of the bridge structure reliability are put forward. Probabilistic analysis design is an analysis technique for assessing the effect of uncertain random input parameters and assumptions on a finite element calculation model. Making use of the Probabilistic Design System, which is offered by the large universal finite element analysis program ANSYS, the reliability analysis of deflection, bend stress and compression member stability of a main truss structure of a 15m-span single-layer single-row prefabricated steel bridge is carried out. Then the corresponding reliability indexes and the bridge system reliability index are obtained. The results show that the ANSYS Probabilistic Design System is exact and reliable in structure reliability analysis of the prefabricated steel bridge.

Key words: probabilistic design, application of ANSYS, reliability analysis, prefabricated steel bridge