受多层地下水影响的深基坑病害的解决方案探讨

Solutions to Problems Encountered in Deep Foundation Pit Affected by Multi-layer Groundwater

近年来北京地区受生态补水的影响,地下水位呈普遍上涨的趋势,给基坑安全带来了较大的威胁。结合北京昌平东小口地区受多层地下水影响的深基坑支护工程,针对施工时遇到的止水帷幕漏水、地面塌陷、桩间流砂等病害问题,通过分析原因,结合现场试验,采取泄水孔减压、L型注浆管“双液”封堵、桩间“支模”等处理方法,解决了基坑开挖过程中的病害问题,确保了基坑在使用过程中的安全。

The groundwater level in Beijing has generally risen under the influence of ecological water replenishment in recent years,which poses a great threat to the safety of foundation pit.A series of problems encountered in the construction of a foundation pit supporting project affected by multi-layer groundwater in Dongxiaokou area,Changping,Beijing,as follows:water stop curtain leaking;surface collapse;sand flowing between pile.Through the analysis of the reasons and combined with field tests,the effective technical treatment measures were adopted such as decompression of drainage holes,"double liquid"sealing of L-shaped grouting pipes,"formwork support"between piles,etc.The disease problems in the process of foundation pit excavation were solved,which ensured the safety of the foundation pit.