Abstract:

A detailed investigation of rail weld irregularity through extensive measurement is conducted at field sites on LIM metro lines. The measurement results show that the rail weld irregularities have four typical forms, i.e., single harmonic form, multiple-harmonic form, overlapping shape and saddle shape. In order to investigate the influence of rail weld irregularities on vehicle-track dynamic performance, a simulation model for an LIM vehicle coupled with the slab track is developed. The deterministic irregularities are as the input of the excitation of wheel-rail interface. The dynamic response of the wheel-rail is analyzed, and the safety limits of the different types of rail weld irregularity are given based on the dynamic simulation. The simulation results show that the wavelength and depth of short wave rail weld irregularity have great effects on wheel-rail interaction. The research results can provide a theoretical reference for the maintenance management of rail weld irregularities on LIM metro line.

Key words: rail weld, safety limits, vehicle-track coupled dynamics, LIM metro vehicles