长江漫滩区多层承压含水层地铁深基坑降水研究  

RESEARCH ON DEWATERING OF SUBWAY DEEP FOUNDATION PIT IN MULTI-LAYERED CONFINED AQUIFER IN THE YANGTZE RIVER FLOODPLAIN AREA

作　　者：郑磊 吴朝阳 王言冲 杨平[2] ZHENG Lei;WU Zhao-yang;WANG Yan-chong;YANG Ping(China Railway Construction Bridge Engineering Bureau Group Co.,Ltd.,300300,Tianjin,China;College of Civil Engineering,Nanjing Forestry University,210037,Nanjing,China)

机构地区：[1]中国铁建大桥工程局集团有限公司,天津300300 [2]南京林业大学土木工程学院,南京210037

出　　处：《建筑技术》2025年第7期852-856,共5页Architecture Technology

摘　　要：以南京地铁某车站为例,通过定义减压井插入第二承压含水层深度D与第二承压含水层厚度L的比值为插入比D/L,用Visual Modflow软件模拟不同插入比的降深效果,得到最优减压井深度,并通过工程实测检验合理性。同时探究减压井数量、滤管长度及止水帷幕深度对降水效果的影响优化降水方案。结果表明:当插入比D/L位于4/9~7/9时,基坑内达到所需降深效果,且插入比为5/9时降深效果最佳;基坑降水达到降深的时间随减压井数量增加呈衰减型规律,存在最优减压井数量;基坑降深效果随滤管长度增大呈抛物线型规律,考虑成本,宜选8 m长滤管;止水帷幕深度越大,降深效果越好,且当止水帷幕插入含水层后,降深效果提升尤为显著;根据减压井深度与止水帷幕深度耦合的曲线可得符合降深要求的二者组合。Taking a certain subway station in Nanjing as an example,the ratio of the depth D of the pressure relief well inserted into the second confined aquifer to the thickness L of the second confined aquifer is defined as the insertion ratio D/L.Visual Modflow software is used to simulate the depth reduction effect of different insertion ratios,and the optimal depth of the pressure relief well is obtained.The rationality is verified through engineering measurement.Simultaneously explore the impact of the number of pressure relief wells,filter tube length,and waterproof curtain depth on the precipitation effect and optimize the precipitation plan.The results show that when the insertion ratio D/L is between 4/9 and 7/9,the required depth reduction effect is achieved in the foundation pit,and the best depth reduction effect is achieved when the insertion ratio is 5/9;The time for foundation pit dewatering to reach the desired depth decreases with the increase of the number of relief wells,and there exists an optimal number of relief wells;The depth reduction effect of the foundation pit follows a parabolic pattern as the length of the filter tube increases.Considering the cost,it is advisable to choose a filter tube with a length of 8 meters;The greater the depth of the waterproof curtain,the better the depth reduction effect,and when the waterproof curtain is inserted into the aquifer,the depth reduction effect is particularly significantly improved;According to the coupling curve between the depth of the relief well and the depth of the waterproof curtain,a combination of the two that meets the requirements for depth reduction can be obtained.

关 键 词：长江漫滩地区 基坑降水 多层承压含水层 

分 类 号：TU74[建筑科学—建筑技术科学]