Increasing track stability in the zone of joints due to the use of elastic under sleeper pads

Abstract

Questions to optimize track stiffness on concrete sleepers were constantly in the area of attention of domestic and foreign experts in the field of track facilities. To slow down the degradation of track (railway track on crushed stone ballast), it is essential to apply under-sleeper pads. Foreign experience shows that in all sections with installed pads there is a significant decrease in the rate of track deterioration, reduction of track settlement, correction of track stiffness, vibration reduction. In the context of growth of axle loads and load intensity in rail transport requirements for track superstructure become more demanding. In this regard, especially for freight routes abroad large assortment of under-sleeper pads is used. In 2014 studies on the effect of application of under-sleeper pads to track operation began at the Test Loop of JSC “VNIIZhT”. During track alignment in joint irregularities test samples of elastic under-sleeper pads of Russian production was laid in the test section. Pads were with different stiffness and thickness. At the moment, loads of more than 300 million gross tons were put on laid structures. It is shown that at the joints of test section abrasion degree of ballast becomes significantly less compared with conventional joints. Material for production of samples with different shape factor was selected on the basis of calculation of minimum rigidity of vibroisolating under-sleeper pads. Graphic test dependencies are shown, confirming the correctness of the calculation.