Improving the dynamic stability of wagons when transporting rock mass

Purpose. To theoretically substantiate and develop technical solutions to increase the dynamic stability of wagons when transporting rock mass by reducing the amplitudes of body vibrations and optimizing the interaction parameters in the “track ‒ wagon ‒ cargo” system. Methodology. The work uses a systematic approach using classical mechanics methods to construct differential equations of motion, numerical integration (Runge‒Kutta method) and the finite element method to analyze the stress-strain state of structures. The mathematical model takes into account a multi-stage dynamic system (up to 12 degrees of freedom), random track irregularities and the mobility of bulk cargo. Findings. As a result of the study, the dependencies between the parameters of the spring suspension and the level of dynamic stability of wagons were established, and the feasibility of using progressive stiffness characteristics and improved vibration dampers was substantiated. Constructive solutions using composite materials are proposed, which provide a reduction in the dynamics coefficient by 12–17 % and a reduction in life cycle costs by 12–15 %. Originality. The scientific novelty consists in the development of an integrated mathematical model of wagon dynamics, which takes into account the interaction of the “track ‒ wagon ‒ cargo” system, the random nature of disturbances and the variable center of mass of bulk cargo. Approaches to assessing the stability against overturning and optimizing the parameters of composite load-bearing structures and spring suspension have been improved. Practical value. The practical significance of the work lies in the possibility of implementing the proposed constructive and technological solutions to modernize the existing wagon fleet, increase traffic safety and reduce operating costs. The results obtained can be used in the design of new wagons and the improvement of systems for diagnosing the technical condition of rolling stock in mining transportation conditions.