集束钢管桩用于房屋群桩基础主动桩基托换技术  

Active Pile Foundation Underpinning Technology of Bundled Steel Pipe Pile for Building Pile Group Foundation

作　　者：雷丹 Lei Dan(Beijing Construction Engineering Group Co.,Ltd.,Beijing 100055,China)

机构地区：[1]北京建工集团有限责任公司,北京100055

出　　处：《市政技术》2022年第11期85-90,共6页Journal of Municipal Technology

摘　　要：在地下交通工程施工中,常遇到隧道结构需要穿越地面建筑既有桩基等问题,当隧道掘进无法避让这些桩基时,通常采用主动桩基托换技术加以处理。但由于房屋内部具有低净空有限空间的特点,若使用大直径桩,其成孔是工程中的难题,若采用集束钢管桩,则可以化大截面桩为小截面桩,从而克服该难题。因此,以广州市三社大楼群桩主动桩基托换为例,通过采用MIDAS GEN软件建立有限元模型进行计算分析,再结合分组顶升和受力转换工序、桩基沉降数据分析,成功完成了桩基托换体系转换;总结出建筑物群桩主动桩基托换关键技术,包括有限空间情况下桩基类型、设备选型、托换体系设置及转换、立柱应力分析对比和顶升结束标准。该托换技术可为类似工程的设计与施工提供借鉴和参考。During the construction of underground traffic engineering,it is often encountered that the tunnel need pass through the pile foundation of the existing buildings.When the pile foundations can’t be avoided by tunneling,the active pile foundation underpinning technology is usually applied.Due to the low indoor clearance and limited space of buildings,pore forming of the large diameter pile foundation is a challenging task.The application of bundled steel pipe pile is able to solve the problem by transforming the large cross-section of pile to smaller ones.Taking the active pile foundation underpinning of Sanshe building group in Guangzhou as an example,the finite element model is established by MIDAS GEN to calculate and analyze.Combined with group jacking,transformation process of stress and analysis of pile foundation subsidence data,the transformation system of pile foundation underpinning is successfully performed;The key techniques for active foundation underpinning of building groups,which consist of pile type,machine and device selection,underpinning settings and transformation,comparison of stress of pillars and the criteria of jack-up finalization in finite space,are concluded in this paper.It is expected that the technology will provide support and reference for the design and construction of the similar projects.

关 键 词：群桩 主动桩基托换 同步顶升 盾构隧道 托换体系转换 集束钢管桩 

分 类 号：U231.3[交通运输工程—道路与铁道工程] TU753.3[建筑科学—建筑技术科学]