嵌入式轨道槽内结构优化设计

嵌入式无砟轨道具有养护维修工作量小、结构稳定等特点，还具有良好的减振降噪性能，特别适应城市轨道交通运营需求，广泛应用在现代有轨电车线路建设中.由于嵌入式轨道的结构特点，其优化重点在槽内结构型式及包覆钢轨的高分子复合弹性体.利用有限元软件ANSYS对嵌入式轨道进行动、静态分析.在拓扑优化的基础上，根据城市轨道交通成本、安全、噪声、振动等功能要求构建轨道结构功能优化目标函数，对嵌入式轨道槽内结构进行优化设计.研究结果表明:针对槽型轨减少靠近轨腰与轨底连接处的复合材料，可以在保证轨道刚度前提下，尽可能节省成本；考虑降噪性能、隔振效果高分子复合材料包覆钢轨高度不宜降低，即应使其完全包覆钢轨；一般地段承轨槽宽度宜在200～220 mm；对于隔振要求严格的区域，增大承轨槽宽度是提高轨道结构隔振效果最有效的手段；复合材料弹性模量选取时，在保证轨道横向刚度的前提下，减小轨道板混凝土结构的应力水平. 

Optimization Design for Internal Structure of Embedded Rail Trough

Embedded ballastless tracks are stable, low maintenance, and good at shock absorption and noise reduction, such that it accommodates the requirements of urban rail transit operation, and has been widely used in the construction of modern tram lines. Owning to the structural characteristics of embedded tracks, its optimization focuses on the trough structure and the polymer composite covering the rail. In this work, the static and dynamic behaviors of embedded ballastless tracks are analyzed by using the finite element software ANSYS. On the basis of topology optimization, given the requirements of cost, safety, noise, and vibration on the urban rail transit, the structure of embedded rail trough is optimized. The results indicate that less composite material at the junction of embedded rail waist and bottom saves the cost while guaranteeing track stiffness. Instead of being lowered in height, polymer composite material should cover the rail completely to decrease the noise and vibration. The width of the bearing slot should range between 200 and 220 mm at normal parts. Increasing the width of the bearing slot is the most effective measure to reduce the vibration in the areas subject to strict vibration requirement. The elastic modulus of the composite material should be chosen to ensure the track transverse stiffness and reduce the stress level of concrete track slab.