偏心对全金属装配式基础抗拔性能影响研究

Numerical Simulation Study on the Effect of Eccentricity on the Uplift Bearing Performance of All-Metal Assembly Foundations

为探究偏心对全金属装配式基础承载性能的影响,利用AnsysWorkbench建立双轴对称(A类,偏心距e_(x)=e_(y)=0)、单轴偏心(B类,偏心距e_(x)=0,e_(y)=0.1~0.6 m)及双轴偏心(C类,偏心距e_(x)=e_(y)=0.1~0.6 m)三类全金属装配式基础与土体模型,以上拔水平力组合荷载为试验工况对基础进行分析,研究基础的位移特性、整体应力及底板变形情况。研究表明,偏心距为0.3 m的单轴偏心基础竖向位移最小为8.83 mm;B、C两类偏心基础屈服时的荷载随偏心距增大呈先增后减的变化,偏心距为0.3 m的单轴偏心基础屈服时荷载最大约为990 kN;基础底板的极差值随偏心距呈先减后增的变化,偏心距为0.3 m的单轴偏心基础底板变形极差值约为1.8 mm。综合比较三类基础发现,单轴偏心基础在组合荷载作用下承载性能较好,其中偏心距为0.3 m的单轴偏心基础是最适宜的全金属装配式基础偏心结构型式。

In order to e_(x)plore the influence of eccentricity on the load-bearing properties of all-metal assembly foundations,three types of all-metal assembly foundation and soil model(biaxial symmetry(Type A,eccentricity e_(x)=e_(y)=0),single-axis eccentricity(Type B,eccentricity e_(x)=0,e_(y)=0.1~0.6 m)and biaxial eccentricity(Type C,eccentricity e_(x)=e_(y)=0.1~0.6 m))were established using Ansys workbench.The foundation with the condition of uplift combined with horizontal loading was analyzed to study the load and displacement characteristics of the foundation,the overall stress and the deformation of the bottom plate.The results show that the minumum vertical displacement of the single-axis eccentric foundation with an eccentric distance of 0.3 m is 8.83 mm.The load on the B and C eccentric foundations when yielded increased first and then decreased as the eccentricity increased.Uniaxial eccentric foundation with eccentricity of 0.3 m bore the largest load when yielded,about 990 kN.The worst value of foundation slab deereascs first and then increases with eccentricty.The deformation of the single-axis eccentric foundation slab with an eccentricity of 0.3 m is about 1.8 mm.Comprehensive comparison of three types of foundation shows that the uniaxial eccentric foundation has better bearing capacity under the combined force,and the uniaxial eccentric foundation with eccentricity of 0.3 m is the most suitable eccentric structure type of all-metal assembly foundation.