超深基坑双道地下连续墙的降水变形性状分析  

Analysis of Deformation Characteristics of Double Diaphragm Walls under the Dewatering for a Deep Excavation Project

作　　者：杨锦健 YANG Jinjian(Shanghai Tunnel Engineering Co.Ltd.,Shanghai 200082)

机构地区：[1]上海隧道工程有限公司,上海200082

出　　处：《土工基础》2024年第3期437-442,共6页Soil Engineering and Foundation

摘　　要：降水工作是保证基坑开挖顺利的重要举措,也是引起围护结构变形的重要原因。以上海市苏州河深层排水调蓄管道超深基坑为依托,分析了双道地下连续墙“双帷幕体系”坑内疏干降水的变形性状,结果表明:地下连续墙随着基坑的开挖降水呈现向基坑内的“鼓肚形”变形,且在降水井滤管埋深范围内出现了局部位移峰值,最大位移的深度多集中在55~66 m的深度范围内,最大位移仅为7.9 mm。坑边地表竖向位移随着远离基坑而呈现减小的趋势,在离基坑边约30 m外而趋于稳定,且在靠近基坑边缘10 m范围内的地表均处于隆起的状态。第二道地下连续墙侧移峰值在8~24 m的深度范围内,变形受坑内降水的直接影响小。The rapid development of cities has made the surface construction space increasingly limited,and the requirements for the development and construction of underground space are gradually increasing.Dewatering is a necessary measure to en-sure the smooth excavation of foundation pits,and it is also an important reason for the deformation of retaining structures.Based on the deep foundation pit of Suzhou River's deep drainage and storage pipeline in Shanghai,the deformation characteris-tics of the dewatering in the"double water-resisting system"of double diaphragm walls were analyzed.The results showed that the diaphragm wall showed a"bulge-shaped"deformation towards the foundation pit with the excavation and dewatering,and local displacement peaks appeared within the depth range of the filter pipe in the well.The depth of maximum displacement was mostly concentrated in the range of 55-66m,and the maximum displacement was only 7.9mm.The vertical displacement of the surface at the edge of the pit showed a decreasing trend away from the foundation pit and stabilized at about 30 meters.The surface within 1o meters of the edge of the foundation pit was in a raised state.The peak displacement of the second diaphragm wall was within the depth range of 8-24m,and the deformation was less directly affected by the dewatering in the pit.

关 键 词：超深基坑 双道地下连续墙 降水 围护变形 

分 类 号：TU443[建筑科学—岩土工程]