三维温度荷载下双块式无砟轨道结构动力响应

研究目的:本文利用ABAQUS有限元软件建立CRTSⅠ型双块式无砟轨道结构温度荷载-落轴冲击耦合模型,结合试验数据,探究不同细致化温度荷载对双块式无砟轨道结构落轴冲击动力响应的影响。研究结论:(1)当道床板表面温度高于内部温度时,钢轨加速度变化较道床板表面温度低于内部温度更显著,轨枕向下加速度、道床板向上加速度分别增加13倍、42倍;(2)当道床板表面温度低于内部温度时,轨枕向上加速度、道床板向下加速度分别增加9.5倍和25倍;(3)当道床板表面温度高于内部温度时,钢轨向下位移减小95%,轨枕及道床板向下位移均为0 mm,轨枕及道床板向上位移分别增加85倍和378倍;(4)当道床板表面温度低于内部温度时,钢轨、轨枕及道床板向下位移分别增加1.01倍、4.3倍和4.91倍,轨枕及道床板向上位移均为0 mm;(5)本研究成果可为我国大温差地区无砟轨道线路平顺性研究提供参考。

Dynamic Response of Double-block Ballastless Track Structure under Three-dimensional Temperature Load

Research purposes:Based on experimental results on three-dimensional temperature and falling axial impact loading on CRTSⅠdouble-block ballastless track structure,a combined temperature and axial impact coupled model was established using ABAQUS finite element software.The aim is to explore how different detailed temperature load influences the dynamic response of CRTS I double-block ballastless track falling axle impact model.Research conclusions:(1)When the ballast bed surface temperature is higher than its internal temperature,the change of rail acceleration is more significant as compared to when the surface temperature is lower than the internal temperature.Also,the sleeper downward and ballast bed upward acceleration increases 13 times and 42 times respectively.(2)When the surface temperature of ballast bed is lower than the internal temperature,the sleeper upward and ballast bed downward acceleration increases 9.5 times and 25 times respectively.(3)When the surface temperature of ballast bed is higher than the internal temperature,the downward displacement of rail reduced by 95%,while the downward displacements of sleeper and ballast bed are 0 mm,and the upward displacements of sleeper and ballast bed increase 85 times and 378 times respectively.(4)When the surface temperature of ballast bed is lower than the internal temperature,the downward displacements of rail,sleeper and ballast bed increase 1.01 times,4.3 times and 4.91 times.However,the upward displacements of sleeper and ballast bed remain 0 mm.(5)The research results can provide references for studying smoothness of CRTS I double-block ballastless track structure under in large temperature difference areas in China.