A multi-objective optimisation method of rail combination profile in high-speed turnout switch panel

Abstract

This paper presents a multi-objective optimisation method considering the switch and stock rail profiles in the switch panel. Based on the non-uniform rational B-spline (NURBS) theory, a parameterised model of the measured turnout profile is constructed to determine the variables. This study selects the vehicle dynamic performance and wheel-rail contact damage as the objective function to establish a multi-objective optimisation mathematical model that is solved using NSGA-II. Overall performances of the measured profile and the optimised profile are compared and evaluated for two aspects, dynamic performance and wheel-rail contact damage. The following are the conclusions: The maximum lateral vibration acceleration of the axle box is reduced from 2.64–2.09 m/s², which has a 20.83% decrease. Concerning wheel-rail contact damage, the maximum wear index is reduced from 13.46–11.47 N, the reduction is 14.78%. At the same time, the cumulative surface rolling contact fatigue (RCF) is reduced from 8.29×10⁻⁵–7.38×10⁻⁵. This article can provide a profile repair method for worn turnouts, which can maximise the comprehensive performance of the turnout within a limited amount of grinding, and can reduce the wheel-rail contact damage of the turnout while taking into account driving stability.

KEYWORDS:

• High-speed turnout
• multi-objective optimisation
• contact characteristics
• dynamic performance
• contact damage

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The research and development efforts have been supported by the National Natural Science Foundation of China (52122810, 51978586, U1734207, 51778542) and the Technology Research and Development Programme of China National Railway Group Co., Ltd (J2021G013, P2021T013, L2021G001) and Technology Research and Development Programme of China Academy Of Railway Sciences (2021YJ022).