邻近地铁侧超深悬臂基坑围护方案研究

Research on Supporting Scheme of Deep Cantilever Excavation near Subway

摘要:

随着城市地下空间的充分利用，新的地下工程问题也逐渐产生。基坑开挖深度达到了11.25 m，并且紧邻运营中的地铁，而且现场不具备支撑和拉锚条件，只能采用悬臂式的围护型式，这对设计和管理提出了很高的要求。通过各类技术措施，从多方面综合考虑，利用现场条件，采取了合理的围护形式，严控现场管理，有效地减小了墙后荷载，把基坑开挖对周边环境的影响降到最低。工程结束后再用监测数据与有限元分析结果进行对比，验证了围护形式以及施工过程的合理性。

Abstract:

With the full utilization of urban underground space, the new underground engineering problems are gradually emerging. The excavation depth of the foundation pit has reached 11.25 m, and it is adjacent to the operating subway. Moreover, there are no conditions for support and anchoring in the site, so only the cantilevered enclosure type can be adopted, which poses the high requirements for design and management. Through various technical measures, comprehensively considering from the multiple aspects, and utilizing the site conditions, the reasonable enclosure form is adopted for this foundation pit, and the on-site management is strictly controlled so as to effectively reduce the load behind the wall, and minimize the impact of excavation on the surrounding environment. After the completion of the project, the monitoring data is compared with the results of the finite element analysis in order to verify the rationality of the enclosure form and construction process.