A Comparative Test of the Mechanical Properties for New Mesh-Type High-Damping Rail Pad and Traditional Rail Pads

The commonly used rail pads for urban rail transit fastener systems include prismatic and grooved rail pads. To reduce pad stress, improve the damping effect, and improve the usage rate of elastic materials, the research team proposed a new mesh-type rail pad (NMTRP) and mesh-type high-damping rail pad (MTHDRP). According to the finite element calculation, the mesh-structured elastic pad has the advantages of uniform stress distribution and high material usage. The MTHDRP has a significantly lower stress level than the traditional rail pad because of the damping block, which is beneficial for prolonging the service life of the rail pad. The research team has processed the NMTRP and MTHDRP through research on the formula and processing technology of the rubber materials. The rail pad’s static/dynamic stiffness test revealed that the NMTRP and MTHDRP have lower static and dynamic stiffness than the traditional rail pad. Furthermore, the MTHDRP has the lowest dynamic-to-static ratio (1.43), indicating a better dynamic stiffness retention capacity than the other three rail pads. The MTHDRP has better vibration damping performance, as evidenced by the hammer test of the rail pad, which revealed that its damping ratio is significantly higher than those of the other three rail pads. Furthermore, its vibration acceleration time and frequency domain signal amplitudes at the rail, clip, track bed, and ground are significantly lower than those of the other three rail pads. Analysis of the 1/3 octave frequency band of the acceleration signal indicates the vibration levels of the MTHDRP at the rail, clip, track bed, and ground are 4.31, 4.37, 4.21, and 1.43 dB lower than those of the prismatic rail pad, respectively. This shows that the vibration reduction effect of the MTHDRP is superior to that of the other three rail pads, and the installation of the MTHDRP can better protect the foundation underneath the rail. In summary, the MTHDRPs have better stiffness, damping and vibration reduction performance than traditional rail pads and have broad application prospects in urban rail transit fastener systems.