盖挖逆作地下工程变形及AM桩应用效果分析  

Analysis on deformation and application effect of AM pile of underground project constructed by top-down method

作　　者：鲍艳[1,2] 张恒[1,2] 陶连金[1,2] 边金[1,2] 

机构地区：[1]北京工业大学城市与工程安全减灾省部共建教育部重点实验室,北京100124 [2]北京城市交通协同创新中心,北京100124

出　　处：《黑龙江科技大学学报》2017年第1期64-68,共5页Journal of Heilongjiang University of Science And Technology

基　　金：国家自然科学基金项目(51208016);国际交流合作项目(51528801)

摘　　要：大规模开挖基坑时,地连墙水平位移及构件间差异沉降过大,导致基坑失稳。依托某AM桩大型盖挖逆作法地下工程,通过有限元软件MIDAS-GTS模拟地下连续墙水平位移及构件间的差异沉降,研究施工过程的沉降变化规律以及AM桩的应用效果。结果表明:楼板对地下连续墙的水平位移、弯矩及结构构件间的差异沉降有良好的限制作用。差异沉降及顶板弯矩均在地下三层开挖后达到最大值,则该阶段为施工过程最不利阶段,应及时进行地下三层底板的浇筑以减小施工风险。相同模型,采用AM桩与等直径桩相比,差异沉降及弯矩均出现一定程度减小,证明AM桩承载力更好,可有效提高结构稳定性。该研究可为类似工程提供参考。This paper is an effort to address the foundation pit instability due to a great horizontal displacement of the diaphragm wall and the differential settlement between the members, as can be seen in large scale excavation of foundation pit. The research building on AM pile large underground engineering project using the top-down method and employing the finite element software MIDAS-GTS is focused on the law behind the change in horizontal displacement of diaphragm wall, differential settlement between members as the construction process goes on, as well as the application effect of AM pile. The results demonstrate that the floor has a better limiting effect on the horizontal displacement and the bending moment of the diaphragm wall and the differential settlement between the structural members ; the maximum value occurring in differential settlement and roof bending moment following the excavation of the third layer suggests the most unfavorable stage of the construction process, resulting in the necessity that third floor should be poured in time to reduce the construction risk; and an AM pile gives the model a smaller differential settlement and bending moment than does equal diameter pile, a proof that the AM pile features a better bearing capacity and promises an improved structure stability. The research may provide a reference for similar projects.

关 键 词：基坑 盖挖逆作法 水平位移 差异沉降 AM桩 

分 类 号：TU753[建筑科学—建筑技术科学] U231.4[交通运输工程—道路与铁道工程]