A rail pad, also known as a rail rubber plate, is placed between the rail tie plate and the foot of the rail. It's made of an elastic polyurethane mat to cushion and protect the sleeper top from wear and impact. The rail pad's stiffness improves the elasticity of the ballast superstructure, reducing shock and vibration in the rail system. This upgrade provides greater passenger comfort and minimizes wear on the superstructure. The enhanced elasticity also benefits the wear of superstructure components and rolling stock. The rail pad is usually secured within a fastening system using screw spikes or rail bolts into the sleeper ties. The use of rubber or plastic in rail pad construction aims to dampen the shocks or vibrations caused by passing trains. The initial low stiffness design ensures substantial relative deformation under spring clip toe loads, maintaining close contact with the rail despite vertical movements.
