双块式无砟轨道裂纹对道床板受力的影响分析

Analysis of Stress State of Track Slab under the Influence of Structure Cracking of Bi-block Ballastless Track

基于路基上双块式无砟轨道的计算力学模型,针对道床板不同宽度和深度情况下的表面裂纹和贯通裂纹,分析在列车荷载作用下道床板开裂前后对道床板受力性能的影响以及在轴向温度荷载作用下含裂纹的道床板受力情况。结果表明,在列车荷载作用下,含裂纹的无砟轨道与无裂纹的无砟轨道相比,道床板混凝土应力有小幅度增加,纵向钢筋应力随裂纹深度的增加而逐渐增大;在轴向温度荷载作用下,随着裂纹宽度的增大,道床板混凝土拉应力及钢筋应力变化较小。

Based on mechanical calculation model of bi-block ballastless track, focusing on both the surface cracks and the through-cracks at track slab with different cracking widths and depths, this paper analyzed the effect on track slab＇s stress state before and after the track slab cracking under the action of train load, and also analyzed the stress distribution of cracked track slab under the action of the most unfavorable axial temperature load. The results show that, in comparison with the un-cracked ballastless track, and under the action of train load, the concrete stress of the track slab of the cracked ballastless track will increase a little, and the longitudinal stress of steel bar will increase with the increase of crack depth. Under the axial temperature load, with the increase of crack width, the concrete＇s tensile stress and the steel bar＇s stress of the track slab will have relatively small change.