某深基坑工程堵漏实例及分析

Case History of a Seepage Stoppage Method for a Deep Excavation Project

为保护地下水资源以及防止坑内降水对基坑周边环境的影响,基坑支护工程大多需要设置止水帷幕,止水帷幕的形式主要是水泥土桩,如搅拌桩、旋喷桩等。止水帷幕渗漏是深基坑工程的主要危险源,会对工程和周边环境造成影响。结合某深基坑工程渗漏事故,重点阐述在基坑抢险过程中所采取的堵漏方法及实施效果,实践证明,对于基坑止水帷幕的轻微渗漏,可采取“内疏内堵”的处理方法;对于较为严重的渗漏,应采取“外截内堵”的处理方法,并且要因地制宜的选择“外截”方法,突出处理的及时性。

To protect the groundwater resources and prevent the impact of the dewatering inside the excavated area on the sur-rounding environment,most the deep excavation support projects need to setup the groundwater stop curtains,which are main-ly in the form of cement mixed soil system,such as soil-cement mixed columns;jet grouting columns,etc.The groundwater curtain stopping leakage is the main hazardous source of deep excavation projects,which will have a great impact on the project and the surounding environment.Combined with the leakage hazards of a deep excavation project,this paper focuses on the plugging method and the implementation effect adopted in the mitigation process of the excavation.Facts have proved that for the minor seepage of the groundwater stop curtain of the excavation system,the treatment method of"internal drainage and in-ternal plugging"can be adopted;For more serious seepage,the treatment method of"external stopping and internal plugging"should be adopted,and the method of"external stopping"should be selected in accordance with the local conditions to highlight mitigation process.