摘要
针对路桥过渡段的不均匀沉降问题,通过建立轨道路基分析模型,结合大型商业软件ANSYS的APDL语言,应用迭代接触算法和单元生死技术模拟搭板与填土之间接触和脱空的不同受力状态;并基于地基均匀沉降和不均匀沉降两种模式,考虑搭板受力与变形的耦合,分析了搭板的受力特性与适应性。受力特性分析表明:随着脱空区长度的增加,搭板及轨道板板底纵向应力增加;板底最大纵向应力的载荷位置在桥台与1/2倍板长之间,且随着脱空区长度的增加,最不利载荷位置与桥台的距离增加;搭板发生完全脱空时,板长且厚的搭板的底部纵向应力比板短而薄的大。适应性分析表明:长度为6 m的搭板适用于处理地基沉降在5mm以内的桥头路段;长度为8 m的搭板适用于处理地基沉降在10 mm以内的桥头路段;长度为10 m的搭板适用于处理地基沉降在15 mm以内的桥头路段。
In view of different settlements of the transition section, through the establishment of track roadbed model, by using large scale commercial software ANSYS APDL language and the contact iterative computing method, the element of lifedeath technology, the different mechanics states of contact and the separation between slab and filling are simulated. On the basis of different foundation settlement modes, the coupling action of slab internal force and deformation is put into consideration, then the mechanics property and adaptability of rigid arrowheaded approach slab are obtained. The analysis of mechanics property shows: with the increase of the separation region length, the longitudinal stress at the bottom of the track slab and the approach slab will also increase. The loading position of the maximum flexural-tensile stress at the bottom is between the abutment and the 1/2 of the slab length, when the length of the separation region increases, the most disadvantageous load position will go away from the abutment; when the slab is completely isolated, the longer and thicker of the slab, the vertical stress at the bottom of the plate will be larger. The compatible analysis indicates that: the slab length about 6m is suitable for treating the foundation when the settlement value is less than 5 mm, and 8m for 10 mm, 10 m for 15 mm correspondingly.
出处
《城市轨道交通研究》
北大核心
2012年第4期61-66,共6页
Urban Mass Transit
关键词
高速铁路
过渡段
刚性楔形搭板
受力特性
high-speed railway
transition section
rigid arrow-headed approach slab
mechanics property