超厚砂层的深大基坑工程降隔水方案选型  

Dewatering Design Comparisons in Deep Excavations in Thick Sandy Soils

作　　者：彭戡 PENG Kan(Zhengzhou Financial Island Construction&Development Group Co.,Ltd.,Zhengzhou 450000)

机构地区：[1]郑州金融岛建设发展集团有限公司,郑州450000

出　　处：《土工基础》2021年第6期686-689,731,共5页Soil Engineering and Foundation

摘　　要：郑东新区龙湖金融中心外环建筑群项目位于郑州市郑东新区中原科技城北龙湖金融岛,共由24个地块组成,基坑总面积达28.52万m^(2),挖深约12.5 m~20 m。基坑面积广阔,周边环境条件复杂,需针对超厚砂层潜水含水层采取安全经济合理的地下水控制措施。基坑实施前通过单井试验获得巨厚潜水含水层的水文地质参数,确定了合理的帷幕设计深度。由于隔水帷幕需穿越超过20 m厚且标贯指标较高的细砂层,因此在环境保护要求高区域采用成墙质量优异、止水效果好的TRD等厚度水泥搅拌墙隔水帷幕施工工艺,其余侧采用常规的三轴水泥土搅拌桩,达到经济合理、安全可靠的降隔水实施效果。Longhu Financial Center Outer Loop Building Group Project is located in Zhengdong New District,Zhengzhou City.The entire development consists of 24 land blocks.The total area of the deep excavation is 285,200 m^(2),and the excavation depth is between 12.5 and 20 meters.The deep excavation project is very large,and the surrounding environmental conditions of the proposed excavated area are complicated.It is necessary to develop a safe,cost-effective and efficient groundwater control measures for the construction in thick sand aquifer layers.Before the implementation of the excavation procedures,a series of single dewatering well tests were conducted to obtain the hydrogeological parameters of the thick phreatic aquifer,to determine the reasonable design of the seepage cut-off wall.Since the groundwater cut-off curtain needs to penetrate the 20 meters thick fine sand layer with high SPT N values,the installations technique of Trench Cutting Re-mixing Deep Wall was used in areas with high environmental restriction requirements.Conventional three-axis cement-soil mixing piles were applied in the other areas.

关 键 词：基坑工程 群井试验 TRD等厚度水泥土搅拌墙 地下水控制措施 

分 类 号：TU473[建筑科学—结构工程]