摘要
为研究地层厚度非均匀性对基坑支护结构稳定性以及支护结构内力、变形的影响,以郑州市某深基坑工程桩锚支护结构为研究对象,提出了非均匀地层基坑支护稳定性计算方法,通过MIDAS软件对实际非均匀地层和简化后的均匀地层两种情况下基坑支护结构进行三维有限元数值计算,并进行了基坑监测。研究结果表明:把非均匀厚度地层简化成均匀厚度地层时,基坑不同位置支护桩桩后土压力、弯矩、剪力和位移等呈现不对称分布,从而造成空间上的变形不协调。“非均匀模型”坡顶水平位移和竖向位移最大比“均匀模型”大54.55%和29.08%,而“非均匀地层”模型坡顶位移计算值与实际监测数据更为接近;“非均匀模型”桩身最大水平位移比“均匀模型”大8.3%;同一工况下两种模型土压力变化趋势相似但同一位置其量值上有较大差别;两种模型中桩身最大正弯矩约有3%的差异,桩身最大负弯矩约有7.9%的差异,这与桩后土压力的分布密切相关。
In order to study the influence of non-uniformity of stratum thickness on the stability of foundation pit support structural stability and the internal force and deformation of the support structure,a pile anchor support structure of a deep foundation pit project in Zhengzhou City was taken as the research object,and a calculation method for the stability of foundation pit support in non-uniform stratum was proposed.The research results indicate that when the non-uniform thickness layer is simplified into a uniform thickness layer,the soil pressure,bending moment,shear force,and displacement behind the support piles at different positions of the foundation pit exhibit asymmetric distribution,resulting in spatial deformation disharmony.The maximum horizontal and vertical displacement of the"non-uniform model"slope top is 54.55%and 29.08%greater than that of the"uniform model",while the calculated displacement of the"non-uniform strata"model slope top is closer to the actual monitoring data;The maximum horizontal displacement of the pile body in the"non-uniform model"is 8.3%greater than that in the"uniform model";Under the same working condition,the trends of soil pressure changes in the two models are similar,but there are significant differences in their values at the same location;There is a difference of about 3%in the maximum positive bending moment of the pile body between the two models,and a difference of about 7.9%in the maximum negative bending moment of the pile body,which is closely related to the distribution of soil pressure behind the pile.
作者
史宏博
聂棒
王安明
陈泰霖
康文献
费应春
SHI Hongbo;NIE Bang;WANG Anming;CHEN Tailin;KANG Wenxian;FEI Yingchun(College of Geosciences and Engineering,North China University of Water Resources and Electric Power,Zhengzhou 450046,China;China Construction Fifth Engineering Division Co.,Ltd.,Zhengzhou 450000,China;Henan Vocational College of Water Conservancy and Environment,Zhengzhou 450008,China;Henan Excellent Construction Engineering Co.,Ltd.,Zhengzhou 450016,China;Henan Geology and Mining Construction Engineering(Group)Co.,Ltd.,Zhengzhou 450071,China)
出处
《建筑结构》
北大核心
2023年第S02期2608-2615,共8页
Building Structure
基金
河南省科技攻关计划(182102310745)。
关键词
基坑
均匀地层
非均匀地层
数值模拟
空间变形不协调
foundation pit
uniform stratum
heterogeneous strata
numerical simulation
inconsistent spatial deformation
