摘要
钢栈桥因具有安拆方便、易于回收利用等特点,成为解决盖挖逆作深基坑作业空间有限、基坑出土及施工用料运输困难等难点的重要技术手段。本文针对盖挖逆作富水砂层深基坑钢栈桥的设计与施工进行研究,对钢管柱顶与贝雷梁的连接形式进行探讨,针对性研发出“坡型”连接端。连接端在钢管柱挖出后再进行焊接,保证了钢栈桥安装精度,且提高了施工效率。优化了桩柱支撑的构造方式及施工方法,采用先插法将钢管柱与抗拔桩钢筋笼可靠连接后在施工作业面吊装至设计标高,保证了抗拔桩和钢管柱的垂直度,钢栈桥贝雷梁、钢管柱间支撑随土方开挖分段分层安装,保证了钢栈桥的整体安全稳定性。借助Midas有限元软件对钢栈桥主要构件及钢管柱稳定性进行数值模拟,结果表明,钢栈桥安全可靠,可以满足施工要求。
The steel trestle has become an important technical means to solve the construction difficulties such as the limited working space of the deep foundation pit with cover and cut-top down method,the excavation of the foundation pit and the difficulty of transportation of construction materials because of its convenient installation and disassembly and easy recycling.In this paper,the design and construction of steel trestle for deep foundation pit in water-rich sand layer are studied.The connection form between steel pipe column top and Bailey beam is discussed,and the′slope type′connection end is developed accordingly.The connection end is welded after the steel pipe column is excavated,which ensures the installation accuracy of the steel trestle and improves the construction efficiency.In order to optimize the construction method of pile column support,the steel pipe column and the anti-pulling pile reinforcement cage are reliably connected by the pre-insertion method,and then hoisted to the design elevation on the construction work surface,which ensures the verticality of the anti-pulling pile and the steel pipe column.The Bailey beam of the steel trestle and the support between the steel pipe columns are excavated with the earthwork and installed in sections and layers,which ensures the overall safety and stability of the steel trestle.With the help of Midas finite element analysis software,the main components of the steel trestle and the stability of the steel pipe column are numerically simulated.The results show that the steel trestle is safe and reliable and can meet the construction requirements.
作者
刘甲振
LIU Jiazhen(China Railway 16th Bureau Group Co.Ltd.,Beijing 100018,China)
出处
《铁道建筑技术》
2024年第6期95-98,144,共5页
Railway Construction Technology
基金
中国铁建股份有限公司科技研究开发计划项目(2021-C21)
中铁十六局集团有限公司科技研究开发计划项目(K2020-20A)。
关键词
盖挖逆作
深基坑
钢栈桥
连接端
贝雷梁
数值分析
cover and cut-top down
deep foundation pit
steel trestle bridge
connection end
Bailey beam
numerical analysis
