Durability Validation of Full Vehicle Structures Using Strain Correlation and RLDA-Based Simulations

Durability validation of full vehicle structures is crucial to ensure long-term performance and structural integrity under real-world loading conditions. Physical test strain and finite element (FE) strain correlation is vital for accurate fatigue damage predictions. During torture track testing of the prototype vehicle, wheel center loads were measured using wheel force transducers (WFTs). In same prototype strain time histories were recorded at critical structural locations using strain gauges. Preliminary FE analysis was carried out to find out critical stress locations, which provided the basis for placement of strain gauges. Measured loads at wheel centers were then used in Multi Body Dynamics (MBD) simulations to calculate the loads at all suspension mount points on BIW. Using the loads at hard points transient analyses were performed to find out structural stress response. Strain outputs from the FE model were compared with physical measurements. Insights gained from these comparisons were used to update the model to achieve better correlation with test data.

The findings of this paper establish a robust methodology for improving vehicle durability assessments by enhancing confidence in fatigue life predictions and structural performance. By integrating physical testing and FE simulations, this approach ensures accurate strain correlation and effective validation of long-term performance. It also provides a scalable framework for validating structural changes, supporting lightweight material integration, and enabling Value Analysis/Value Engineering (VAVE) initiatives to optimize cost-effectiveness and performance. This methodology strengthens simulation-driven durability development, offering valuable insights for future vehicle programs.