摘要
根据单元板式无砟轨道不同施工工艺和结构受力特点,采用弹性点支承梁模拟钢轨,用实体单元模拟无砟轨道各结构层;砂浆填充层采用灌注袋法施工时,轨道板和砂浆填充层之间按接触单元处理;砂浆填充层采用模筑法施工时,轨道板和砂浆填充层之间按黏结方法处理;建立相应有限元模型,进行轨道板温度翘曲变形研究。结果表明:砂浆填充层采用灌注砂浆袋法施工时,轨道板在温度梯度荷载作用下产生的翘曲变形大于模筑法施工;采用模筑法施工砂浆填充层时,轨道板的翘曲变形随上下表面温差幅值的变化呈线性关系;而采用灌注砂浆袋法施工砂浆填充层时,轨道板的翘曲变形随上下表面温差幅值的变化呈非线性关系,温差越大,轨道板翘曲变形的变化幅度越大。有限元模型计算的结果与环形铁道轨道板的翘曲变形实测结果基本吻合,验证了模型的合理性和可靠性。
According to the construction technology and structure mechanical characteristics of unit slab track,a beam-solid model on the elastic foundation was established to calculate the temperature warping of the slab.Rails were modeled by discretely supported beams while the bearing layers of slab track were modeled by solid in the model.When building the mortar layer with perfusion bag,slab and mortar layer were not bonded but contacted.If building the mortar layer with molding construction method,slab and mortar layer were bonded.The corresponding finite element model was established to calculate the temperature warping rules of the slab.The result indicates that compared with the molding construction method,perfusing mortar into the bag will cause a larger warping displacement of the slab under the temperature gradient load.If taking molding construction method,the slab displacement amplitude changes with the temperature difference between the top and bottom surface of the slab in a linear way.While taking the perfusion bag method,the relation between the temperature change and the slab warping is nonlinear.The larger temperature difference is,the bigger the slab warping change scope is.The predicted result agrees with the field test data on the slab track. Rationality and reliability of the finite element model are verified.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2010年第3期9-14,共6页
China Railway Science
基金
铁道部科技研究开发计划项目(2007G044-H)
