双块式无砟轨道纠偏修复时道床板结构受力变形行为研究

The Stressed Deformation Evolution Behaviors of Twin-block Ballastless Track Structure in Deviation Rectification

为确保横向顶推纠偏时无砟轨道结构受力合理、不损伤破坏,通过对纠偏过程中CRTSⅠ型双块式无砟轨道道床板应变、既有裂缝及伸缩缝宽度和纠偏量的监测与分析,研究了基于横向顶推力逐级加载控制纠偏时双块式无砟轨道结构道床板受力变形演变行为及纠偏对轨道实体结构的影响。结果表明:通过逐级加载控制,道床板的应变曲线均呈"M"或"W"形,其受拉区、受弯区及反弯点分布规律明显在最大纠偏量达20mm情况下,纠偏修复未造成无砟轨道结构产生开裂或压碎破坏。

To ensure ballastless track structures being reasonably stressed and free of damage and failure in transverse jacking-based deviation rectification,stepwise and controllable transverse jacking stresses were synchronously loaded on the supporting layer and bed slab of a CRTS I twin-block ballastless track.The strains,existing fractures,expansion joints’widths,as well as rectification values of the bed slab and supporting layer were monitored and analyzed during the process.On this basis,investigations were given to the stressed deformation evolution behaviors of this structure and the influences of the rectification on the track structure.The results suggested that:by loading stepwise and controllable stresses,fractures or crushing failures were not observed on the structure as the maximum rectification value reached to 20mm;both of bed slab and support layer showed“M”or“W”-shaped strain curves,on which,tensile zones,bending zones,and anti-bending points distributed by obvious laws.