Objective The imported vehicles in China at the early stage of urban rail transit development are approaching the end of their design lifetime, so it is necessary to carry out relevant structural fatigue status assessment and economic analysis to develop maintenance strategies for this issue. However, there is limited research in China on the fatigue status assessment of riveted structures in urban rail transit vehicles, and relevant foreign standards also lack usable data. Therefore, it is necessary to study the status assessment of the riveted structures and establish a reasonable service status assessment system.

Method Based on a specific railway vehicle, the bolster beam and coupler base beam of the vehicle body’s riveted structure are selected as the research objects. Through finite element analysis, dynamic stress testing and data analysis, riveted structure fatigue test, fatigue lifetime calculation, and rivet status inspections, a comprehensive fatigue status assessment system for the vehicle body’s riveted structures is established. Inspection results show that the rivets are in good condition after service, no deformation, cracking or other abnormal phenomena are observed.

Result & Conclusion  The fatigue lifetime calculation results for the riveted structure indicate that the car body's riveted structure can not only meet its 30-year design life, but also enable the potential of extending its lifetime to 45 years under safe service.The proposed status assessment method for riveted structures can provide a reference for the fatigue status assessment, design optimization and maintenance of similar vehicle structures. Further in-depth researches are still needed on rivet status inspection methods to avoid causing damage to the vehicle structure when obtaining inspection rivets.