落底式帷幕在地下结构永久主动抗浮工程应用中的渗透性研究  

Study on the permeability of closed groundwater cut-off curtain in the active anti-uplifting engineering

作　　者：冯红超[1] Feng Hongchao(BGI Engineering Consultants Ltd.,Beijing 100038,China)

机构地区：[1]北京市勘察设计研究院有限公司,北京100038

出　　处：《工程勘察》2018年第8期24-29,36,共7页Geotechnical Investigation & Surveying

摘　　要：落底式截水帷幕虽然是基坑开挖地下水控制的一种主要方式,但其在结构使用期间仍可以阻断区域地下水与基底地下水之间的水力联系,达到主动抗浮的目的。而基于截水帷幕主动抗浮设计的关键因素是截水帷幕的渗透性研究。本文以北京某工程为依托,对采用的三轴水泥土搅拌桩止水帷幕进行帷幕体渗透性试验研究。首先进行弥散试验,结合试验结果通过数值模型对帷幕体的渗透性进行反演计算;进一步进行水位恢复试验,反演帷幕体及帷幕体嵌固隔水层的渗透系数,并与弥散试验分析结果进行相互校验。最终,根据试验确定渗透系数进行落底式帷幕在建筑永久主动抗浮工程应用的经济性探讨。The closed groundwater cut-off curtain is the main measures to prevent groundwater in deep excavation.The cut-off is still effective to block the hydraulic connection between the groundwater and the water beneath the basement when the structures put in use,so that the purpose of active anti-uplifting can be achieved.The sealing performance of the closed cut-off curtain is the key factor in the active anti-uplifting engineering design.Permeability test on the cement-soil mixture of the three-shaft mixing pile curtain is carried out in Beijing.The dispersion test is carried out firstly,combined with the test results,the permeability of curtain shaft is calculated by numerical model.The groundwater recovery test is then carried out to obtain the permeability coefficient of cut-off curtain and curtain founding strata.The results could be verified each other.The economic contrast analysis of the application of the closed curtain in the permanent anti-uplifting engineering is carried out according to the permeability coefficient determined by the tests.

关 键 词：主动抗浮 截水帷幕 渗透性 弥散试验 水位恢复试验 数值模拟 

分 类 号：TU753.7[建筑科学—建筑技术科学]