中文摘要：

根据路基上CRTSⅢ型板式无砟轨道设计方案,考虑了轨道多层结构间非线性相互作用关系,基于有限元方法建立了不同底座板纵连长度的轨道结构空间耦合模型,计算了轨道结构横向稳定性与整体升降温作用下轨道板、自密实混凝土和底座板的受力与变形,分析了底座板的合理纵连长度。分析结果表明：底座板纵连长度为2块及以上轨道板长度时,可满足结构横向稳定性的要求;在升温45℃荷载作用下,随着底座板长度的增大,轨道板纵向位移线性增大,最大增幅约为58%,但是应力与弯矩变化不明显;自密实混凝土受力与变形的变化幅度较轨道板稍大,最大拉应力为0.949MPa;在降温40℃荷载作用下,底座板应力受纵连长度的影响显著,当长度达到5块轨道板长度时,其纵向拉应力达到2.67 MPa,接近混凝土容许拉应力。综合考虑横向稳定性与结构强度因素,底座板合理纵连长度应控制在2~5块轨道板长度范围内。

英文摘要：

According to the design scheme of CRTSⅢ slab ballastless track on subgrade,the nonlinear interaction between multilayer structures was considered,and the spatial coupled models of track structure with different longitudinal-continuous lengths of bed plate were established based on finite element method.The lateral stability of track structure and the stresses and deformations of slab,self-compacting concrete layer and bed plate under the temperature load were computed,and the reasonable-longitudinal-continuous length of bed plate was analyzed.Analysis result shows that the lateral stability of slab track is satisfied when the continuous length of bed plate is greater than or equal to the connected length of 2track slabs.Under the condition of temperature increasing 45 ℃,when the length of bed plate increases,the changes of stress and moment in track slab are not obvious,while the longitudinal displacement linearly increases,and the maximum increasing value is about 58%.For the self-compacting concrete layer,the changes of stress and deformation are more obvious than the values of track slab,and the maximum value of tensile stress is 0.949 MPa.Under the condition of temperaturedecreasing 40 ℃,the influence of continuous length on the bed plate stress is obvious.When the continuous length of bed plate reaches the connected length of 5track slabs,the longitudinal tensile stress of bed plate increases to 2.67 MPa,which is close to the allowable limit of concrete tensile strength.In summary,based on taking into the factors of lateral stability and structural strength,the reasonable-longitudinal-continuous length of bed plate should be the connected length of 2-5track slabs.7tabs,15 figs,23refs.