Experimental Research on Load Path in Vehicle Frame Bodies

doi:10.3901/JME.2016.10.103

Abstract

Abstract: An experimental method to investigate the load path in a vehicle body frame under certain condition is presented. The mechanical characteristic of vehicle frame is analyzed through strain gauge measurements of stress state at every corner of the key measuring sections. Stress composition is adopted to describe load distribution and internal moment is employed to represent load transfer. Load-carrying factor(LCF) and Christiansen uniformity coefficient(CUC) are used to evaluate the load-carrying capacity of the vehicle body frame. Based on the concept of load path, a modification plan for the vehicle body frame is proposed. The results show that bending stress can be treated as the principle evaluation index of load distribution, and warping stress can be a supplementary tool to observe the direction of load path. In the torsional condition, longitudinal members carry major portions of loads, transverse members and pillar members constitute the anti-torsional rings to share and discharge loads. The anti-torsional rings should exist in the frontal cabin, passenger cabin and rear cabin of vehicle body. If any anti-torsional ring is missing, the load-carrying capacity of the vehicle frame body would be sharply weaken. In the modified version, the load-carrying capacity and the load-distribution uniformity increase of 18.71% and 14.89% respectively. Load path analysis has an essential practical value for vehicle body structure design.

Key words: load distribution, load transfer, load-carrying capacity, vehicle body frame

CLC Number:

U467

TIAN Linli, GAO Yunkai, AN Xiuzhe. Experimental Research on Load Path in Vehicle Frame Bodies[J]. Journal of Mechanical Engineering, 2016, 52(10): 103-112.

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