Crash Response of a Repaired Vehicle - Influence of Welding UHSS Members

Abstract

Automakers generally recommend not to weld structural parts after a vehicle crash, and these should be replaced as a whole part in case of a crash event. Sectioning of these members is also not recommended, and use of the repair manual is mandatory in case of fracture of such parts. However, repair shops may not adhere to these instructions and use incorrect repair procedures on these members which would modify their strength properties. This study analyses the impact of welding structural members in a vehicle like the A-pillar which use Ultra-High Strength Steels (UHSS) for reducing the weight of the vehicle and improving the crashworthiness of the structure. The research conducted in this paper highlights the differences in the crash performance of a repaired vehicle as opposed to baseline injury values for the vehicle. The performance of the modified vehicle when tested for different loadcases shows reduced crash performance as compared to the baseline performance and it can be concluded that welding or sectioning the UHSS parts would influence the crashworthiness of a vehicle. This paper only focuses on structural integrity of the repaired vehicle in a crash event. The performance of the vehicle in occupant injury is kept out of scope for this study.

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A Novel Technique for Modeling Vehicle Crash using Lumped Parameter Models

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Mathematical models for assessment of vehicle crashworthiness: a review

“…The study shows that the model does not need to be too complex unlike the one for full vehicle loadcases, which reduces the computational costs. Recently, FEM has been used by the authors for determining the crash response in welded vehicles which contributed to the development of more stringent norms for improper repairs on UHSS structural members [62].…”