饱和软黏土中梯形浅基础承载特性研究

Study on bearing characteristics of trapezoidal shallow foundation in saturated soft clay

以ABAQUS有限元软件为平台,采用理想弹塑性本构模型模拟了浅基础及周围土体,建立了梯形浅基础的二维有限元模型,研究了不排水饱和软黏土中不同尺寸的梯形浅基础在竖向荷载、水平荷载和弯矩荷载单独作用模式下的地基承载特性,分析了基础侧面倾斜角度和深宽比两个变量对承载力的影响,针对25组模型的地基极限承载力进行无量纲和归一化处理,提出了承载力系数计算公式。数值计算结果表明:梯形浅基础的竖向承载力系数Nc随着基础倾斜角度α的增加呈幂指数函数形式增长,随着基础深宽比d/B的增加呈线性增长;水平承载力系数Nh随着基础倾斜角度α的增加呈幂指函数形式增长,随着基础深宽比d/B的增加呈线性增长;弯矩承载力系数Nm随着基础倾斜角度α的增加呈幂指函数形式增长,随着基础深宽比d/B的增加亦呈幂指函数形式增长。

Based on the platform of ABAQUS,the ideal elastic-plastic constitutive model was used to simulate the shallow foundation and the surrounding soil,trapezoidal shallow foundation of two-dimensional finite element model was established and the bearing capacity characteristics of single function mode were calculated which based on different sizes of trapezoidal shallow foundation in saturated soft clay in vertical load,horizontal load and bending moment load.By the means of dimensionless and normalized processing,the influences of the foundation inclinationαand foundation depth-width ratio d/B on the bearing capacity were analyzed and the bearing capacity calculation formulas on the foundation bearing capacity of the 25 set model were put forward.The numerical results show that the vertical bearing capacity coefficient Nc of trapezoidal shallow foundation increases exponentially with the increase of foundation inclinationαand linearly with the increase of foundation depth-width ratio d/B.The horizontal bearing capacity coefficient Nh increases as a power function with the increase of foundation inclinationαand linearly with the increase of foundation depth-width ratio d/B.The moment bearing capacity coefficient Nm increases exponentially not only with the increase of foundation inclinationαbut also with the increase of foundation depth-width ratio d/B.