摘要
收集了上海软土地区35个具有墙后地表沉降实测资料的深基坑工程案例,从统计角度研究了深基坑的墙后地表变形性状。最大地表沉降随着开挖深度的增大而增大,其值介于0.1%H~0.8%H之间,平均值为0.38%H,其中H为基坑开挖深度。影响因素分析表明最大地表沉降随着墙后软土层厚度的增大而增大,随着坑底抗隆起稳定系数的增加而减小,而与围护墙的插入比及支撑系统刚度的关系不大。最大地表沉降与最大墙体侧移的比值基本介于0.4~2.0之间,其平均值约为0.84。统计了墙后地表沉降的分布模式,给出了墙后地表沉降的包络线。最大地表倾斜量介于0.001~0.017之间,给出了根据最大地表沉降量来预测最大地表倾斜量的统计关系。
The characteristics of ground surface settlement caused by deep excavations in Shanghai soft soils are studied based on a database of 35 case histories.The magnitude of the maximum ground surface settlement generally increases with the increase of excavation depth.Values of the maximum ground surface settlement generally range from 0.1%H to 0.8%H,with an average value of 0.38%H,where H is the excavation depth.The maximum ground surface settlements increase with the increase of the thickness of soft soils above wall toe,but decrease with the increase of the factor of safety against basal heave.The maximum ground surface settlement is independent of the system stiffness of the retaining system and the embedded depth ratio of retaining wall.The lower and upper bound values of the ratio between the maximum ground surface settlement and the maximum lateral displacement of wall are 0.4 and 2.0,respectively,with an average value of 0.84.Distribution of the ground settlement is analyzed.The upper bounds of the ground settlement profiles are proposed for the case histories in Shanghai.The maximum ground surface distortion ranges from 0.001 to 0.017.Relationship between the maximum ground surface distortion and the maximum ground surface settlement is also established.
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2011年第11期1659-1666,共8页
Chinese Journal of Geotechnical Engineering
基金
上海市科学技术委员会科技攻关重点项目(08201200900)
关键词
深基坑
地表沉降
统计分析
软土
deep excavation
ground settlement
statistical analysis
soft clay