Investigation of Functionality of Vehicle Crumple Zones Recovered after a Traffic Accident

It is fairly common for a used vehicle to have a history of damage related to traffic accidents. Post-accident repair of a vehicle is associated with both technical and economic challenges. Safe operation is mentioned primarily in the technical requirements that restrict further use of the vehicle. Here, forecasting the behaviour of the restored safety elements during another traffic accident should be addressed from the theoretical perspective. During a collision, the longitudinal members lose local stability due to the compressive impact load and partially absorb the impact energy due to the plastic deformations taking place during buckling. Recent research has placed a considerable focus on the analysis of this process, and guidelines have been developed for the design of these elements. However, the accumulated data on the effect of potential operational damages and the behaviour of the damaged elements during a traffic accident are insufficient. Moreover, no theoretical models have been developed, and the experimental investigations are insufficient. Investigating changes in the properties of elements of the crumple zone by using materials of different mechanical characteristics or changing the geometry is the essential part of this paper and forms the basis for the study of key deformation properties of the elements. This study designed numerical models allowing for forecasting of the longitudinal member and other structural elements of the vehicle in case of collision with an obstacle. The methodology was designed to forecast the amount of energy absorbed by the thin-walled sections used in the vehicle safety cage and the course of deformation under impact loads that caused stability loss. The effect of potential damages, such as geometric deviations and changes in the characteristics of materials and fabricated joints, was identified on the deformation of the restored safety elements.