Reliability Index Allocation for Switch Tamping Machines Based on Belief Reliability

The switch tamping machine is a crucial large-scale railway maintenance equipment characterized by complex features such as multi-level systems, multi-disciplinary scope, and high component correlation. In the development of new electric-driven switch tamping machines, conducting reasonable reliability index allocation is essential to ensure accurate system design and safe operation. Existing reliability allocation methods face challenges, including unreasonable series assumptions, difficulties in achieving allocation results, and a lack of objectivity in the allocation process. To address these issues, this paper proposes a belief reliability allocation method based on performance margin and causal importance, grounded in belief reliability theory. By analyzing the functional principles of the switch tamping machine, we establish a substance-energy-information-related model for the system to evaluate the causal importance of subsystems. Subsequently, an optimization model for performance margin allocation is developed, linking system reliability indices to subsystem design requirements. A case study on a new electric-driven switch tamping machine validates the effectiveness of the proposed method. Reliability verification calculations further demonstrate the rationality of the allocation results.