ABSTRACT
The paper presents the results of sub-rail pads field tests to assess the effect of the stiffness and number of standard and prototype sub-rail pads on the level of vibration transmitted to the track when trains pass in the rail junction area. In order to achieve this goal, vertical vibration accelerations arising from trains passing in the rail joint area were measured with different numbers of standard sub-rail pads and high elasticity pads. At all investigated types of rolling stock (passenger train, Lastochka, Sapsan) with standard vibration damping pads before their replacement in the area of the rail joint on the subgrade top 2-3 times higher amplitudes of vertical vibration accelerations were fixed than at the distance of 7 sleepers from the joint. Comparison of vibration acceleration amplitudes in the rail joint area with different numbers of dampers showed that 7 dampers installed on each side of the rail joint are most effective. A comparison of vibration-dynamic impact level of on the ballast in the area of the rail joint depending on the type of rolling stock with different axle load and speed has shown, that Lastochka and Sapsan have a greater impact on the track than passenger trains with a speed of 90 km/h and a load of 150-160 kN per axle. Vibration acceleration amplitudes in the ballast layer with 7 pads of increased elasticity Sylodyn NF (experimental) are 1.4-2 times smaller than those of standard - CP-204-M-ARS (standard).
