Condition Assessment Method of Rail Welded Joint Equipment Based on Confidence Level

Abstract

Objective To address the incomplete assessment system for seamless rail equipment conditions in China, it is necessary to establish an equipment condition assessment method for rail welded joints. Method The allowable deviations for the flatness of high-speed rail and welded joints specified by current Chinese regulations are elucidated. Taking a high-speed railway line for 13 years running in China as study case, the flatness data of the line rail welded joints is analyzed, and it is observed that the rail joint flatness detection data generally conforms to normal distribution. Based on the principles of normal distribution and confidence intervals, the mean value/standard deviation assessment and confidence level assessment two methods are compared. The rail welded joint equipment condition assessment method based on confidence level is proposed, along with the corresponding assessment criteria for high-speed railway rail equipment. Result & Conclusion This method can objectively and intuitively reflect rail welded joint equipment conditions, allowing accurate understanding of rail equipment conditions. The method can serve as a good theoretical basis for analyzing the law of changes in rail equipment, as well as formulating standards, plans, and strategies for major and medium maintenance.

Keywords

• urban rail transit
• seamless rail
• welded joint
• flatness
• equipment condition assessment
• normal distribution
• confidence level