盖挖换乘站换乘节点桩柱预留设计及施工技术研究

Research on Technologies for Design and Construction of Reservation of Piles and Columns of Interchange Nodes of Interchange Stations Constructed by Cover-and-cut Method

为解决盖挖换乘站桩柱预留型式换乘节点相关技术难题,采用结构分析、理论计算及实践验证等方法对盖挖换乘站桩柱预留型式换乘节点设计及施工技术进行了系统地研究与总结。主要包括:1)结合远期站施工工况,利用有限元结构计算软件对换乘节点在不同施工工况下的受力形态进行分析,得出了换乘节点处构件随远期站施工工况转换引起的内力变化趋势及构件控制工况;2)系统地研究了逆作法支撑柱与近、远期站构件的连接方式,得到了立柱桩与不同构件的连接大样;3)为节省投资、方便施工,探索了利用围护结构支撑换乘节点的方法;4)为控制节点的沉降与变形,考虑工序转换的影响,给出了节点处远期站的施工方法及施工注意事项。

The technologies for the design and construction of the reservation of piles and columns of interchange nodes of interchange stations constructed by cover-and-cut method are studied and summarized by means of structure analysis, theoretical calculation and practical validation, in order to find solutions for the reservation of piles and columns of the interchange nodes of interchange stations constructed by cover-and-cut method. The contents of the paper are as follows： 1 ） The stressing conditions of the interchange node under different construction conditions are analyzed by means of FEM structure calculation software in consideration of the construction conditions of the long-term station, and the internal force variation trend and the control conditions of the structural elements of the interchange nodes along with the construction of the long-term station are obtained ; 2） The connection between the support columns of the stations constructed by top-down method and the structural elements of the short-term and long-term stations are studied systematically and the details of the connections between the vertical columns and piles and the structural elements are obtained ; 3 ） The solution to support the interchange nodes by the retaining structure is discussed, so as to reduce the cost and to facilitate the construction ; 4） The construction program of the long-term station, as well as the points to which attention should be paid during the construction, is proposed under the consideration of the working step conversion, so as to control the settlement and deformation of the interchange nodes.