钢管插入式基础抗拔承载性能数值模拟

Numerical Simulation of Uplift Bearing Capacity of Plug-in Steel Tube Concret Basis

为研究输电线路杆塔三角锚固盘钢管插入式基础在承受上拔荷载时锚固盘的受力性能,使用有限元分析软件对钢管插入式基础进行数值模拟分析,研究了锚固件尺寸、混凝土强度、钢管截面和混凝土柱截面对试件抗拔承载性能的影响。结果表明:使用三角锚固盘能够改善锚固盘与钢管焊接部分的应力集中情况,显著提升钢管插入式基础的抗拔承载能力,且混凝土强度越高优势越明显;在一定范围内增加锚固盘尺寸可以提高基础抗拔承载力,提高初始刚度和延性系数,超出范围则影响不明显,最佳的锚固盘尺寸由基础混凝土强度决定;增加混凝土强度、钢管截面尺寸和混凝土柱截面尺寸都可以提高基础的抗拔承载力和初始刚度,延性系数则随混凝土强度的提高先减小后增大,随钢管截面尺寸的提高而减小。

In order to study the mechanical behavior of plug-in steel tube concret basis with triangular anchor plate of transmission line tower under uplift load,the finite element analysis software was used to simulate the steel tube insert foundation,and the influence of anchor size,concrete strength,steel tube section and concrete column section on the uplift bearing capacity of the specimen was studied.The results show that:the triangular anchor plate can improve the stress concentration of the welding part between the anchor plate and the steel pipe,significantly improve the uplift bearing capacity of the plug-in steel tube concret basis,and the higher the concrete strength is,the more obvious the advantage is.Within a certain range,increasing the size of the anchor plate can improve the uplift bearing capacity of the foundation,and improve the initial stiffness and ductility coefficient,and beyond the range,the influence is not obvious,the most obvious.The results show that the optimal anchorage plate size is determined by the concrete strength of the foundation.Increasing the concrete strength,steel tube section size and concrete column section size can improve the uplift bearing capacity and initial stiffness of the foundation,while the ductility coefficient first decreases and then increases with the increase of concrete strength,and decreases with the increase of steel tube section size.