Investigation on the Formation and Evolution of Rail Corrugation at Rail Welded Joints Under Multiple Wheel Passages

A vehicle–track system finite element (FE) model coupled with a rail surface wear model and an offline rail profile update strategy have been developed to study the formation and evolution of rail corrugation at rail welded joints under multiple wheel passages. The FE model calculates the vehicle–track dynamics and rail surface wear. Fourier series is used to fit the dynamic wear, and then the rail profile is updated offline by modifying node coordinates based on the fitted dynamic wear. The FE model’s reliability for wheel–rail contact solutions was confirmed through comparison of computed contact stresses (FE model vs. CONTACT). The vehicle–track dynamic behaviors of the FE model have been validated with the measured wheel–rail vertical force at corrugated track. It is found that after multiple wheel passages, rail surface develops corrugation with a dominant wavelength of approximately 150 mm. The corrugation depth grows gradually with the number of wheel passages at a gradually decreasing rate, whereas the depth of the welded joint gradually decreases. The welded joint and corrugation move toward the rolling direction during wheel passages. The corrugation is the most severe when the weld is located above the sleeper. Controlling the welded joint wavelength to 30 mm can significantly suppress corrugation development. Under a constant traction level, a lower friction coefficient will result in more severe rail corrugation.