Experimental research of the stress-strain state of the energyabsorbing center sill of an open wagon

Abstract The development prospects of the railway industry require the introduction of the scientific solutions to improve the operational efficiency of rail transport facilities. One of the ways to achieve this objective is to increase the strength of rail transport facilities, which can reduce the maintenance costs and enhance the reliability in operation. The loading on the bearing structures of wagons in operation can be reduced by applying closed profiles filled with energy-absorbing material in wagon frame components. The article presents the results of the experimental substantiation of the application of filler for the center sill in the open wagon. The research was made for the end part of the frame as the most loaded component regarding the longitudinal operational forces. The research included two stages: determination of the stress-strain state of hollow samples (rods) and ones with filler. The deformation behavior of the test samples was studied by means of resistance strain gauges with an active gauge length of 10 mm and resistance of 100 Oh; they were calibrated in advance. The resistance strain gauges were mounted according to the bridge connection. The areas, on which the resistance strain gauges were glued, were determined by the results of the finite element modelling of the samples in Lira-SAPR and SolidWorks Simulation. The results of the research demonstrated that with filler in the rod the stresses were reduced by 5% in comparison with stresses in the rod without filler. The difference between the experimental and theoretical strength calculations for the rods was about 3%. The research results will contribute to the creation of wagons with improved technical and economic indicators, reducing the costs of their maintenance by reducing the number of damages and improving the environmental friendliness of freight transportation by rail.