Efficient Railway Turnout Design: Leveraging TRIZ-Based Approaches

Abstract

This study focuses on the design and improvement of railway turnouts, which are critical yet complex parts of the railway infrastructure. As they are responsible for track discontinuity and potential derailments, turnouts pose significant challenges in terms of slack, misalignment and rail breakage. A new concept related to the design of turnouts, including switches and crossings, is presented in this paper. The application of TRIZ (Theory of Inventive Problem Solving) principles, specifically the use of the contradiction matrix, was instrumental to achieving these innovative designs for railway systems and represents the main contribution of the paper. Based on the systematic use of the TRIZ principles, the proposed design addresses the problems associated with switches and crossings by replacing the classic frog with a movable element that sits in the crossing gap and reduces the existing gap, thus minimising the length of the rail gap and, consequently, providing greater contact with the rail, minimising wheel impacts on the rail gap and, consequently, decreasing the risk of derailment. By reducing rail contact forces, which are a major contributor to derailments, the risk of derailment is reduced. This study also introduces a new design for the switch rail system using a piston mechanism with an up and down stroke, which is accompanied by a rotating motor at the top for controlled movement. Finally, numerical simulations were performed to validate the proposed designs.