温度及收缩荷载下路基上双块式无砟轨道力学及裂缝特性研究

Study on mechanics and crack behavior of twin-block ballastless track on subgrade under the temperature and shinkage load

温度及收缩荷载是双块式无砟轨道的重要荷载。以路基上双块式无砟轨道为研究对象,道床板中钢筋用梁单元模拟,道床板、双块式轨枕、支承层以实体单元模拟,道床板混凝土与钢筋、支承层与路基之间的连接用弹簧单元模拟,建立了考虑混凝土开裂的钢筋与混凝土相互作用有限元力学模型,并编制了相应的计算程序。研究了温度及收缩荷载下路基上双块式无砟轨道力学及裂缝特性,分析了双块式无砟轨道类型、道床板厚度、道床板配筋率及道床板裂缝间距对双块式无砟轨道力学特性及裂缝宽度的影响。

Temperature and shrinkage load are the important load of twin-block ballastless track.The paper regarded twin-block ballastless track on subgrade as the research object.The steels in track concrete layer were simulated by beam element;the track concrete layer,the twin-block sleeper,the support layer were simulated by solid element;the concrete and the steels in the track concrete layer,the support layer and subgrade were simulated by the spring element.A mechanics model of interaction of the steel bar and the conncrete which considered the cracking of the concrete was established and the corresponding computer program was developed.This paper analyzed mechanics and crack behavior of twin-block ballastless track on subgrade under the temperature and shrinkage load,studied the effects of twin-block ballastless track type,the thickness of the roadbed slab,the reinforcement ratio of the roadbed slab and the crack interval of the roadbed slab on twin-block ballastless track mechanical behavior and the crack width.