中文摘要：

地铁工程施工一个关键的问题是地铁基坑如何抗浮。本文在介绍常用基坑抗浮措施的同时,提出了在封底混凝土与围护结构地下连续墙之间设置抗剪槽与抗浮桩相结合的抗浮方案。首先研究了抗浮桩的工作机理,然后对抗剪槽的设计进行重点分析,最后结合北京地铁8号线永定门外站的工程实例,应用MIDAS/GTS有限元软件作模拟分析。分析结果表明,抗剪槽和抗浮桩共同抵抗地下水浮力,减少了抗浮桩的数量及长度,降低了施工难度,节约了工期,降低了工程成本。

英文摘要：

Anti-floating design of foundation pit is a key issue in metro construction. The common anti-floating measures for foundation pit were presented and the anti-floating scheme setting the combination of shear slot with anti-floating pile between subsealing concrete and underground continuous wall with enclosure structure was put forward in this paper. The working mechanism of anti-floating pile was studied, the shear slot design was analyzed, and the simulation analysis was implemented with MIDAS/GTS finite element software by taking the Yongdingmen station in Beijing subway line No. 8 as an example. The results show that shear slot and uplift piles resist the groundwater buoyancy, which could reduce the quantity and length of uplift piles, decrease the construction difficulty, save the construction time and the engineering cost.