In this paper, the stress-erection process of STRARCH system was simulated by using dynamic relaxation method(DRM) and elasto-plastic beam-column element. The Stressed-Arch(STRARCH) system is a unique and innovative structural form and member prestress comprising prefabricated plane truss frames which are erected by a post-tensioning stressing procedure. The shape and member force of erected STRARCH frame are determined from the initially unstable assembled STRARCH frame by using so called stabilizing process analysis. The plastic hinge concept are applied with large deformable elasto-plastic beam-column element for the tubular top chord becoming to be curved, often causing yielding over a substantial portion of its length, during the post-tensioning stress-erection process. Finally, the verification of proposed approach for stress-erection of STRARCH is evaluated by comparing the numerical results with predicted value of tendon force and member forces.