Mechanical Properties And Monitoring Methods Of High-speed Railway Tumout On Bridge

In recent years, China’s high-speed railway has developed rapidly, along with widely application of welded turnout on bridge. When welded turnout is laid on bridge, the high-speed railway ballastless track structures have a complex relationship with each other, integrating technical points of welded line, welded turnout and ballastless track. Therefore, aiming the complex structures of high-speed railway welded turnout on bridge, the interaction relationship and mechanical properties of bridge, welded line, welded turnout and ballastless track should be studied under high-speed operating conditions. And force sensitive indicators, sensitive areas, measuring contents and testing arrangement of high-speed railway welded turnout should be mastered. By studying monitoring technology of high-speed railway turnout on bridge, the mechanical properties can be focused and measured in the case of long-term vise and high load, grasping the state of its application and safetyIn this paper, the following work has be done:(1)By reading numbers of paper, the high-speed railway turnout track system on bridge is detailed studied, as well as theoretical research and testing data of welded turnout on bridge are collected. Taking full account of the structural characteristics of welded turnout on bridge, a high-speed railway No.42welded turnout-ballastless track-bridge statics/dynamic simulation model is established by ANSYS and ABAQUS software.(2)Using the established statics model, the mechanical properties of high-speed railway welded turnout on bridge are analyzed under temperature loads, train flexural loads and train braking loads. The force and deformation of rail (including basic rail, point rail and switch rail), ballastless track and bridge are especially analyzed. Studies have shown that:the temperature loads have a greater impact on welded turnout on bridge, while the train flexural loads and braking loads have a smaller impact; under different loads, both of the point rail tip and switch rail tip have bigger longitudinal displacement and longitudinal force, on the contrary, the vertical relative displacements are smaller; under different loads, the longitudinal displacement and longitudinal force of the both ends of ballastless track and bridge are large.(3)Using the dynamic model, considering statics model calculate-analysis results and existing monitoring data, point rail, switch rail, ends of beam and middle span are established as sensitive areas, while the temperature, longitudinal force, longitudinal displacement of point rail, switch rail, bridge, ballastless track are established as sensitive indicators,as well as wheel-rail vertical and lateral forces and so on.(4)Based on fiber monitoring method, a monitoring program for welded turnout on bridge is developed which is located on contact line between Tianjin and Shanghai in Tianjin South railway station of Beijing-Shanghai high-speed railway. In the program, the monitoring contents, monitoring methods, measuring points and data processing methods are analyzed and elaborated.