Scientific rationale for the use of perforation beams in the bearing structure of a modernized railroad flat wagon for container transportation

This study investigates processes related to the occurrence, acceptance, and redistribution of loads in the supporting structure of a railroad flat wagon. The task addressed is to improve the technical and economic indicators of the modernized flat wagon for container transportation by reducing its tare. To this end, the stress distribution fields in the modernized railroad flat wagon structure were determined. It was established that the main longitudinal beams of the frame have a strength reserve, which is due to the underutilization of railroad flat wagon bearing capacity. This leads to an excess sprung mass of its supporting structure. Therefore, it is proposed to introduce perforation in the walls of the main longitudinal beams of a railroad flat wagon. To substantiate this solution, the strength of the bearing structure of a railroad flat wagon was calculated. It was established that the maximum stresses in the bearing structure are 13.6% lower than the permissible ones. The design service life of a railroad flat wagon is at least 32 years. The biaxiality calculation of the bearing structure showed that its greatest values are reached in the middle parts of girdle beams. A special feature of the proposed solution is that it makes it possible to improve the technical and economic indicators of the modernized railroad flat wagon with minor capital investments. The scope of practical application of the results is railroad transport. A condition for practical use of the results is symmetrical loading of the bearing structure of a railroad flat wagon with cargo. The results of the research could contribute to improving the efficiency of container cargo transportation along international routes. In addition, the results might prove useful for designing and fabricating new structures of railroad flat wagons, as well as for modernizing existing ones