砂土中水平矩形锚板竖向拉拔承载全域内三维统一力学模型与承载力计算方法研究  

Three-dimensional unified mechanical model and calculation method of uplift capacity of horizontal rectangular anchor plate in the whole region in sand

作　　者：胡伟[1,2] 王辉 姚琛 郝冬雪[4] 史旦达 HU Wei;WANG Hui;YAO Chen;HAO Dong-xue;SHI Dan-da(Hunan Province Key Laboratory of Geotechnical Engineering Stability Control and Health Monitoring,Hunan University of Science and Technology,Xiangtan,Hunan 411201,China;School of Civil Engineering,Hunan University of Science and Technology,Xiangtan,Hunan 411201,China;China Railway Major Bridge Reconnaissance&Design Institute Co.,Ltd.Chongqing Branch,Chongqing 400020,China;School of Civil Engineering and Architecture,Northeast Electric Power University,Jilin,Jilin 132012,China;College of Ocean Science and Engineering,Shanghai Maritime University,Shanghai 201306,China)

机构地区：[1]湖南科技大学岩土工程稳定控制与健康监测省重点实验室,湖南湘潭411201 [2]湖南科技大学土木工程学院,湖南湘潭411201 [3]中国中铁大桥勘测设计院集团有限公司重庆分公司,重庆400020 [4]东北电力大学建筑工程学院,吉林吉林132012 [5]上海海事大学海洋科学与工程学院,上海201306

出　　处：《岩土力学》2023年第6期1811-1825,共15页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52178332,No.52078108)。

摘　　要：水平矩形锚板竖向拉拔属于典型的三维问题,但极限状态下锚周土体滑动面形态受锚板长宽比、埋深比两个变量共同影响,表征难度大。结合ABAQUS软件三维数值模拟和二维滑动面分析结果,三维滑动面在其埋深范围内任一水平剖面上的几何形态可用4段分别与锚板长边、短边平行且相等的直线段以及4段1/4圆弧线组成的闭合图形描述;直线段与对应锚边的水平距离由长边中心竖向对称面内的滑动面决定,该二维滑动面形态仅取决于埋深比,可使用对数螺旋线形态函数进行表征。构建出了水平矩形锚板竖向拉拔承载三维力学分析模型,分析了该模型存在的4种工况。结合模型的分解与合并开展隔离体的力学极限平衡分析,推导建立了水平矩形锚板竖向拉拔承载力计算方法,该方法可在长宽比和埋深比全域范围内使用。通过与5个试验案例,3种计算方法的对比分析表明,新方法在各种密实状态砂土地基中均表现最好,具有很好的适用性。Uplift of the horizontal rectangular anchor plate is a typical three-dimensional problem.However,it is difficult to characterize the sliding surface of soil around the anchor plate in the limit state for its shape is affected by a combination of the length-width ratio and embedment ratio of the anchor plate.Combining the results of ABAQUS 3D numerical simulation and 2D sliding surface analysis,it is found that the geometric form of the 3D sliding surface in any horizontal section within its buried depth range can be described by a closed graph,including four segments of straight lines parallel and equal to the long and short sides of the anchor plate respectively and four segments of 1/4 arc.The horizontal distance between the straight line and the corresponding anchor edge is determined by the 2D sliding surface in the vertical symmetric plane in the center of the long edge.The shape of this 2D sliding surface depends only on the embedment ratio,and it can be characterized by the logarithmic spiral morphological function.Based on these understandings,a three-dimensional mechanical analysis model of uplift bearing capacity of the horizontal rectangular anchor plate was constructed for the first time,and four cases of the model were analyzed.Combining the decomposition and merging of the model,the mechanical limit equilibrium analysis of the isolation body was carried out.Then,the calculation method of uplift bearing capacity of the horizontal rectangular anchor plate was deduced.It is applicable in the whole range of the length-width ratio and embedment ratio.Compared with five test cases and three other calculation methods,the results show that the proposed method has the best performance in all kinds of sand ground with various relative densities,which shows good applicability.

关 键 词：矩形锚板 竖向拉拔 滑动面 力学模型 承载力 

分 类 号：TU441[建筑科学—岩土工程]