Stress estimation in fifth wheel coupling system using finite element model validated by experimental modal test

Ebrahimi, Reza; Shafiei, Alireza; Fatemi, Seyed Masoud

doi:10.22064/tava.2026.2066958.1271

Stress estimation in fifth wheel coupling system using finite element model validated by experimental modal test

Document Type : Case Study

Authors

Reza Ebrahimi ¹

Alireza Shafiei ²

Seyed Masoud Fatemi ²

¹ Mechanical Engineering, Faculty of Engineering, Yasouj University, Yasouj, Iran

² Research and Development Department, Espahan Koosha Company, Isfahan 81611-98371, Iran

10.22064/tava.2026.2066958.1271

Abstract

In the heavy vehicle transport industry, the fifth wheel coupling system is used as important component for connecting the semi-trailer with the tractor. Misfunction, corrosion or fracture of the fifth wheel can affect the stability and consequently the safety of the heavy vehicles. During operation, the fifth wheel experiences different loading conditions. So, a reliable model which represents stresses due to acting forces on the fifth wheel coupling system plays a significant role. For this purpose, first, controlled vibration experiments are conducted on a JOST’s fifth wheel coupling system and modal parameters of the system is obtained. Moreover, a finite element model (FEM) is constructed in ABAQUS software and successfully validated by the results of the experimental modal analysis (EMA). Then, the validated FEM is used to achieve the stress distribution in the system for accelerating and breaking conditions. Also, it is found that stresses in the JOST’s fifth wheel coupling system remain below the mechanical strength limit of the material.

Keywords

Fifth wheel coupling system

Experimental modal analysis

Finite element modelling

Stress analysis

Subjects