高速铁路CRTSⅡ型板式无砟轨道高温变形及损伤机理研究

High Temperature Deformation and Damage Mechanism of CRTSⅡ Ballastless Slab Track on High Speed Railway

为研究CRTSⅡ型板式无砟轨道在系统升温及温度梯度共同作用下的温度变形特征及损伤失稳机理,采用有限元分析手段,建立连续12块板总长度约80 m的轨道结构理论分析模型,提出接缝处的钳口形受力机制,并分别对窄接缝均匀和不均匀损伤条件下轨道结构的温度变形特征进行计算分析。结果表明:钳口效应将加速窄接缝的压溃;不同的接缝损伤工况组合引起不同形态的轨道结构变形;板端偏压力线上移进入宽接缝内容易导致板端劈裂。

To study the temperature deformation characteristics and damage mechanism under the joint action of system temperature rise and temperature gradient, the finite element method is used to establish the theoretical analysis model of the ballastless track, covering 12 slabs and about 80 meters length. The jaw stress mechanism at the track joint is put forward to study track structure temperature deformation characteristics with homogeneous damage and inhomogeneous damage of narrow joints. The results show that the jaw effect could accelerate crushing of narrow joints and the combination of different joint damage conditions lead to different forms of track deformation; the up-movement of partial pressure line at slab end into wide joint is likely to cause slab-end cracking.