Load-carrying system of reinforced concrete structure on construction is different from load-carrying system on service life. This temporary load-carrying system is composed of shores and concrete members of early age on construction. Geometrical model and material property of structure are time-varying on construction. Through secondary development of ANSYS, the processes of placing concrete and removing shore are simulated on construction. Critical effect factors are determined through the analysis on mechanical property of temporary load-carrying system, such as shore stiffness, foundation stiffness and diurnal temperature difference. Results of analog calculation to temporary load-carrying system will provide basis for shoring system design and structure reliability analysis on construction.