چكيده به لاتين
In order to attract passengers and cargo, the rail transportation system must be able to ensure the safety of rail routes well. Due to the fact that buckling of railway tracks is one of the most important things that cause the departure of the trains, so it becomes important to prevent it from happening. Since the amount of lateral resistance of the railway track plays a significant role in the possibility of this phenomenon, therefore, one should always ensure that the lateral resistance is sufficient. Researchers have conducted many studies on the factors affecting the lateral resistance of the railway, but the effect of the vertical load caused by the weight of the train on the lateral resistance of the railway has received less attention. In this research, the effect of vertical load on the lateral resistance of the railway with three types of concrete, steel and wooden sleepers was investigated by conducting experiments in a laboratory environment and numerical modeling in Abaqus software. The ballasted panels that were made in a laboratory environment with various types of sleeper include 7 sleepers with a distance of 60 cm.
The studies conducted in this research show that the lateral resistance of the middle sleeper of the panels, on which the vertical load is directly applied, is higher than other sleepers, and as the distance between the sleepers increases from the middle sleeper, its lateral resistance decreases. The amount of increase in the lateral resistance of the middle sleeper of the panels due to the application of a vertical load of 25 tons on the middle of the panel is equal to 145, 88 and 48%, respectively, which shows that the vertical load had the greatest effect on the lateral resistance of the steel sleeper and the least effect on the lateral resistance of the Wooden sleeper. However, in terms of the final value of lateral resistance reached by each of the traverses despite the vertical load, the concrete sleeper with a value of 1698 kg has the largest value and the steel sleeper with a value of 1006.54 kg has the lowest value. Changing the amount of vertical load on the railway panel from 5 to 35 tons showed that with the increase of the vertical load, the lateral resistance of the sleeper also increases, and an almost linear relationship between the vertical load and the lateral resistance was obtained for each of the sleepers. The change of three parameters of ballast, which includes density, modulus of elasticity and adhesion, shows that the change of adhesion parameter has the greatest effect on the value of lateral resistance in the presence of vertical load, and the change of ballast density has the least effect. Changing the amount of friction between the concrete sleeper and ballast from 0.1 to 0.8 showed that the friction between the floor of the sleeper and the ballast has a much greater effect on the lateral resistance with vertical load than the friction between the besides of the sleeper and the ballast. Loading in the form of a bogie on the panel showed that as the longitudinal distance between the wheels of the bogie increases, the amount of increase in lateral resistance in the presence of vertical load also increases, so that for a two-axle bogie with a wheel spacing of 2.5 meters, the amount of increase in lateral resistance of the concrete sleeper, steel and wooden are equal to 80.47, 102.81 and 16.64 percent, respectively. This is while for a bogie with a wheel spacing of 2.8 meters, the amount of increase in lateral resistance has decreased due to the application of vertical load, so that for concrete, steel and wooden sleeper, there has been a 61.9, 74.29 and 14.68% increase in lateral resistance, respectively.
