“坑中坑”二级接力降水施工技术在深基坑中的应用

Application of Pit-in-pit Secondary Relayed Dewatering Construction Technology in Deep Foundation Excavation

针对超大超深基坑降水水位在-30^-40m时,地下水补给性强,导致管井降水效果不理想、成本递增的情况,以沈阳某深基坑降水工程实例作为实践对象,介绍了二级接力降水施工技术的工艺原理及实践效果。结果表明:该基坑采用"坑中坑"二级接力降水方案是可行的,相较于传统基坑外一级降水工艺,二级接力降水工艺加快了施工进度、提高了降水效果、节约了降水成本。

In the large and deep foundation excavation,when the precipitation water level is between-30 --40 m,the groundwater recharge is strong,which can result in undesirable dewatering effect of tube well and cost increase. According to this situation,taking a foundation excavation in Shengyang for example,this paper introduces the technology principle and practice effect of secondary relayed dewatering construction technology. The results show that pit-in-pit secondary relayed dewatering technology is practicable in the foundation excavation,and it has more advantages than conventional onestage dewatering technology in accelerating construction progress,improving effect of dewatering and saving cost of dewatering.