Features:
1. Static stiffness
The static stiffness of the pad under the rail should be 140kN/mm±20kN/mm.
2. Dynamic and static stiffness ratio
The dynamic and static stiffness ratio of the under-rail pad should not be greater than 2.0
3. Fatigue performance
The rate of change of static stiffness of the under-rail pad after 3*106 fatigue tests should not be greater than 20%.