持续高温作用下CRTSⅡ型无砟轨道层间离缝分析
Analysis of interface seam of CRTSⅡ slab track under sustained high temperature

在夏季持续高温天气下，CRTSⅡ型板式无砟轨道由于温度梯度的持续作用，轨道板与砂浆层之间易产生层间离缝。基于现场气温与轨道板温度梯度实测数据，采用有限元建模计算分析持续正温度梯度作用下轨道板与砂浆层间离缝产生和发展的特征。研究结果表明：持续高温天气期间，轨道板温度整体高于气温，且温度力作用过程中正温度梯度虽未超过规范规定的轨道板设计正温度梯度90 ℃/m，但轨道板与砂浆层之间仍能产生层间离缝。通过比较，持续高温与温度梯度90 ℃/m作用下，两者层间损伤程度较为接近，且靠近板角位置层间离缝现象比其他位置更加严重。建议工务部门重视持续高温对无砟轨道工作性能的影响。
Due to the sustained load of temperature gradient, it appears the interface seam between slab and mulsified asphalt cement mortar layer of CRTSⅡ slab track easily under the sustained high temperature in Summer. Based on the field measured data of temperature and slab temperature gradient, the feature of occurrence and development of interface seam under sustained positive temperature gradient load is analyzed by finite element method. The results showed the whole slab temperature higher than temperature，and although the positive temperature gradient has not exceeded 90 ℃/m which is specified by code during the mechanism of temperature stress，it generates interface seam as well. By comparing the affect of sustained high temperature and 90 ℃/m，the interface damage is relatively close. The phenomenon of interface seam which is near the corner of slab is worse than other location. It is suggested the railway engineering department pays attention to the influence of working capabilities of slab track under sustained high temperature