Wheel and rail profile optimisation for a heavy haul network

Abstract

This study presents a systematic framework for optimising wheel and rail profiles and its application in a North American heavy-haul railway. The network suffers from severe low-rail RCF in tight curves with widened gauge, while high-rail damage remains limited due to effective friction management. To address this imbalance, a two-phase optimisation strategy was developed in order to consider the demands and constraints imposed by the stakeholders: first, a wheel profile was designed to reduce low-rail damage across varying gauge conditions while maintaining or reducing high-rail damage in sharp curves; second, two new rail profiles were introduced for mild curves and tangent track to ensure compatibility with the new optimised wheel profile and to reduce contact stresses in these sections. Wheel profile optimisation markedly reduces low-rail subsurface stress, but tread modifications compromise its performance on larger-radius curves. Optimising rail profiles for wide curves and tangent track resolves this shortcoming. Overall, integrated wheel-rail optimisation outperforms wheel-only strategies and is practically achievable via adjustments to existing rail grinding templates, underscoring the value of a system-level approach to managing RCF and wear in heavy-haul operations.