Abstract—Since automobiles have become a major means of transportation, there have been high risks or frequent actual occurrences of accidents due to drivers’ negligence. In general, accidents between vehicles result from collisions at the front, rear, or side sections. In the case of frontal collisions, the safety of passengers may be protected to some extent because of the frontal frame and engine room while in the case of broadside accidents, the stiffness of doors and pillars is a deciding factor in terms of passenger safety. In the case of rear side collisions, the trunk and pack panel protects passengers by absorbing impact. However, most vehicles except large-sized automobiles have no separate frame, involving vulnerable sections structurally. After an accident, the affected vehicle is repaired at a car repair shop. For trunk deformation, the welding section is removed employing a drill and the trunk is replaced, which is followed by welding over the connecting sections. As a result, major parts may be damaged, depreciating the vehicle. Further, vehicle performance may be degraded after the repair, causing safety concerns. This study accordingly includes collision tests simulaing rear-side collision accidents after repair to examine the actual damages upon a collision just as in a real accident. Additionally, the vehicular condition after repair from a collision was interpreted and analyzed through a commercial program. Factors were then interpreted and compared with one another about the F-D curve, effective plastic strain, and force depending on the speed.