平封底加固在深层泉眼止水施工中的成功应用

Successful Application of Flat Back Cover Reinforcement in Deep Spring Water Stop Construction

通过介绍一个约3万m^(2)大型房建项目,在周边楼栋均已建好的情况下,开挖最后一块近900 m^(2)地库基坑时发生多处承压水突涌事故,严重影响了工程进度,最终从安全性、经济性、止水有效性,以及对既有建(构)筑物的影响等方面综合比选,最终采用对环境扰动小的MJS工法进行坑底平封底止水处理方案,有效解决了承压水突涌问题。该项目成功实践可为类似复杂环境下承压水问题的解决提供参考和有益的借鉴。

An about 30 000 m^(2) large building construction project is introduced. Under the condition of the surrounding buildings having been built, several confined water inrush accidents occurred during the excavation of the last basement foundation pit with an area of nearly 900 m^(2), which seriously affects the project progress. The comprehensive comparison is carried out from the aspects of safety, economy,effectiveness of water stop and impact on the existing buildings and structures. Finally, the MJS construction method with small environmental disturbance is adopted for the water-stop treatment scheme of flat back cover at the pit bottom, which effectively solves the problem of confined water inrush. The successful practice of the project can provide the useful reference and experience for the solution of confined water problems in similar complex environments.