Lightweight Design and Structural Finite Element Analysis of a Composite Railway Axle: A Case Study of Iranian Rail-Bus axle

Moradi, Abbas; Shokrieh, Mahmood. M

doi:10.30511/jmms.2026.2081552.1030

Lightweight Design and Structural Finite Element Analysis of a Composite Railway Axle: A Case Study of Iranian Rail-Bus axle

Document Type : Original Article

Authors

Abbas Moradi ¹

Mahmood. M Shokrieh ²

¹ School of Mechanical Engineering, Iran University of Science and Technology

² School of Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran

10.30511/jmms.2026.2081552.1030

Abstract

With population growth and concerns about environmental hazards and resource depletion, attention has turned to the rail transportation industry as a productive sector. As one of the simplest modes of transport, rail plays a crucial role in passenger and freight mobility. In this research, a solid steel axle from an operational rail vehicle in Iran was selected. Based on structural analysis of its mechanical properties and operational conditions, a redesign was undertaken to reduce weight by adopting a hollow configuration. Polymer-based composite materials were employed. The design consists of a pair of steel collars and two composite shafts with different geometries. Static finite-element analysis on the composite axle assembly yielded a Tsai-Wu failure index of 0.36. Maximum von Mises stress in the steel collar was 216 MPa, the static safety factor was 1.94, and maximum shear stress in the adhesive joint was 28 MPa. Modal analysis showed the composite axle natural frequency as 89 Hz, a significant improvement over 68 Hz for the solid steel axle. The lightweight axle mass is 173 kg, a 62% weight reduction. This approach can be applied to design other axles and shafts subjected to bending and torsion.

Keywords

Railway axle

lightweighting

Composite materials

Structural analysis

Finite element