基于双曲线模型的冻土中锚杆荷载传递特性研究  

Load transfer characteristics of anchors in frozen soil based on hyperbolic model

作　　者：董旭光 雷肃 万愉快 孙国栋 DONG Xuguang;LEI Su;WAN Yukuai;SUN Guodong(School of Civil and Hydraulic Engineering, Ningxia University, Yinchuan 750021, Ningxia, China;Ningxia Center for Research on Earthquake Protection and Disaster Mitigation in Civil Engineering, Yinchuan 750021, Ningxia, China;State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China)

机构地区：[1]宁夏大学土木与水利工程学院,宁夏银川750021 [2]宁夏土木工程防震减灾工程技术研究中心,宁夏银川750021 [3]天津大学水利安全与仿真国家重点实验室,天津300072

出　　处：《地震工程学报》2021年第6期1387-1393,共7页China Earthquake Engineering Journal

基　　金：国家自然科学基金(51808302,51968061);宁夏青年科技人才托举工程第三批(TJGC2018093);宁夏大学博士科研启动项目(2017067)。

摘　　要：为研究不同冻结温度及含水率对冻结粉土中锚杆抗拔性能的影响,根据冻土与混凝土接触面的力学特性和变形规律,采用双曲线模型描述锚杆-冻土接触面的剪切特性。基于荷载传递法,建立考虑温度和含水率影响的锚杆荷载传递方程,采用有限差分法进行求解,得到锚固段的剪应力、轴力及承载力计算式;通过ABAQUS数值模拟验证荷载传递方程的合理性,结合算例分析表明:冻土中锚杆抗拔承载力大于常温土,且温度越低承载力越高;在相同荷载作用下,冻土温度越低,轴力沿深度衰减越快,剪应力分布越不均匀;相同冻结温度下,锚杆承载力随含水率的增大呈先增大后减小的趋势;增加锚固体直径能有效地提高锚杆的极限承载力。In this paper,the influence of different freezing temperatures and moisture contents on the anti-pulling performance of anchor in frozen silt was studied.According to the mechanical characteristics and deformation law of the frozen soil-concrete interface,the hyperbolic model was used to describe the shear displacement characteristics of anchor-frozen soil interface.The anchor load transfer equation considering the influence of temperature and moisture content was established based on the load transfer method.The calculation formulas of shear stress,axial force,and bearing capacity of the anchorage section were then obtained by using the finite difference method,and the rationality of the equation was verified by ABAQUS numerical simulation.The results showed that the uplift bearing capacity of anchor in frozen soil is greater than that at normal temperature.The lower the temperature,the higher the bearing capacity.Under the same load,the attenuation rate of axial force along the depth increases with the decrease of frozen soil temperature.Under the same freezing temperature,the bearing capacity of anchor increases first and then decreases with the increase of moisture content.The ultimate bearing capacity of the anchor can be effectively improved by increasing the anchor diameter.

关 键 词：冻土 锚杆 双曲线模型 荷载传递机理 有限差分法 数值模拟 

分 类 号：TU473[建筑科学—结构工程]