In consideration of the metro design and operation in Guangzhou, this paper establishes a finite element model analyzing monolithic track bed of underground line, analyzes the stress state of upper and lower surface of track slab. Finally, it presents the proper schemes with regard to the mesh reinforcement setting there, the design relating to connection between tunnel structure and the track bed in non-shielding section, applied types of railway sleeper and drainage way, etc.rnThe analytical result shows that with action of live load of train, upper and lower surface of track slab may be in tension or compression in both longitudinal and lateral directions, as a result, it is appropriate for the slab to be provided with double layer of reinforcement. The length of sleeper has little effect on slab stress and stress is increasing as the increase of the width of sleeper. For the underground monolithic track bed, besides convenient construction and dimensions required by fasteners anchoring shoud be guaranteed, small-size reinforced concrete long sleeper is recommended. In order to prevent water seepage at deformation joint on the bottom plate, in track bed design, the connection between track bed and foundation shall be strengthened with drainage and water guiding measures so that accumulated water could be led into the bed surface or drainage ditch timely and effectively. Herein bilateral drainage ditch is recommended. In order to solve poor drainage at the ditch just outside the circular tunnel, the structural height of the track may be increased properly to enlarge section size of the ditch at this segment. The height is advised to be increased to 780 mm.%根据广州地铁设计与运营的情况,建立了地下线整体道床有限元分析模型,探讨了整体道床钢筋网设置方式、非盾构地段隧道结构与整体道床连接设计、轨枕、排水方式等的合理方案.分析结果表明:在列车活载作用下,道床板的上下表面在纵横向都有受拉或受压的可能,道床板宜双层配筋;轨枕的长度对道床板应力影响很小,而道床板应力随着轨枕宽度的增加而增大,地下线整体道床在保证施工方便及扣件锚固需要的尺寸外,建议采用尺寸较小的钢筋混凝土长轨枕.为预防结构底板变形缝处渗水病害,在道床设计时,应加强道床与基础的连接,考虑疏水、导水措施,以便及时有效地将积水引至道床表面或排水沟.地下线整体道床推荐采用双侧水沟,为解决圆形隧道曲线外侧水沟排水不畅的问题,可适当提高轨道结构高度,以加大圆形隧道地段的水沟断面尺寸,建议轨道结构高度提高至780 mm.
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