Fatigue Damage on Vehicle’s Body Shell: A Correlation between Durability and Torsion Tests

The purpose of this article is to present a correlation between fatigue damage caused on vehicle′s body shell during durability tests at a road simulator and during torsion test of the body shell at a test machine. The durability test alternates a variety of road tracks, paved and unpaved, as well as loading condition of the vehicle, whether loaded or empty. The torsion test consists of a test machine in which it is possible to apply a torsion moment on the body shell.

Through the results obtained in the vehicle’s durability test it is possible to associate a real number of kilometers with an estimated number of cycles at the body shell torsion test. This way, it is intended to optimize the response time for the technical approval of the components related to the body shell, resulting in a reduced development cost.

This correlation is based on material’s strength fundaments, cumulative damage under cyclical loadings related to fatigue, in accelerated tests on mechanical components and in the experimental stress analysis.