深厚淤泥土深长基坑开挖对邻近建筑的影响  

Influence of Deep Foundation Pit Excavation on Adjacent Buildings under Unfavorable Geological Conditions of Deep Silt Soil

作　　者：杨忠平[1,2,3] 刘浩宇 周小涵 张益铭[1,2,3] 常嘉卓 Yang Zhongping;Liu Haoyu;Zhou Xiaohan;Zhang Yiming;Chang Jiazhuo(School of Civil Engineering,Chongqing University,Chongqing 400045,P.R.China;Key Laboratory of New Technology for Construction of Cities in Mountain Area(Chongqing University),Ministry of Education,Chongqing 400045,P.R.China;National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas(Chongqing),Chongqing 400045,P.R.China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]山地城镇建设与新技术教育部重点实验室(重庆大学),重庆400045 [3]库区环境地质灾害防治国家地方联合工程研究中心(重庆),重庆400045

出　　处：《地下空间与工程学报》2022年第3期1015-1024,共10页Chinese Journal of Underground Space and Engineering

基　　金：重庆市自然科学基金(cstc2021jcjy-msxmx0558)。

摘　　要：沿海区域存在大量淤泥土层,其通常表现出高压缩性、流变性及触变性等不良工程地质性质。因此,深厚淤泥土深长基坑开挖面临着极高施工风险,对周边环境的影响显著。为进一步阐明深厚淤泥土深长基坑开挖施工力学效应,依托某深基坑工程,通过有限元三维数值模拟,揭示了淤泥土深长基坑开挖对邻近建筑的影响规律。结果表明:深厚淤泥土层的存在使基坑开挖影响区的水平影响区域明显增大,竖向影响区域所受影响较小,在水平距离150 m、深度85 m范围内土体皆受基坑开挖影响;基坑以及建筑轮廓凹凸部出现应力集中,在淤泥土层,地连墙以及既有隧道墙板应力集中处的水平位移存在明显突变;既有隧道水平位移和沉降曲线呈“中间大,两头小”的特征;大桥变形随开挖深度增加而变大,桥桩在淤泥土层的水平位移明显增大,最大水平位移达5.33 mm,最大沉降达9.92 mm。In coastal area, there are many muddy soil layers with high compressibility, rheology and thixotropy bad engineering geological properties. Therefore, the deep silt soil deep excavation is facing high risk construction and has significant effects on the surrounding environment. In order to further clarify the deep silt soil mechanical excavation of significant effect, based on a deep foundation pit project, through the finite element three-dimensional numerical simulation, the influences of silt soil deep excavation on nearby architectural structures are revealed. The results show that: the existence of deep silt soil makes the horizontal influence area of the foundation pit excavation increase obviously, while the vertical influence area is less affected. In the horizontal distance of 150 m and the depth of 85 m, the soil and structures are all affected by the foundation pit excavation. Foundation pit and outline in concave and convex, architectural structures, discover stress concentration. Therefore, in the land of silt soil layer depth, wall and both the horizontal displacement of tunnel wall panel with obvious mutation;both the horizontal displacement and settlement curve tunnel is the characteristics of the "large in the middle and small at both ends". The deformation of the bridge increases with the increase of the excavation depth and the horizontal displacement of the bridge piles in the silt soil depth increases obviously with the maximum horizontal displacement of 5.33 mm and maximum subsidence of 9.92 mm.

关 键 词：基坑工程 深厚淤泥土 水平位移 沉降 数值模拟 

分 类 号：U121[交通运输工程]