压力集中型预应力锚索剪应力有限元分析

Finite Element Analysis of Shear Stress in Prestressed Pressure-type Anchor Cable

在详细分析压力集中型预应力锚索结构特征基础上,利用有限元软件进行模拟和分析该种锚索受力特征。在分析中采用整体式初应变方法来考虑混凝土和钢筋(即将混凝土和力筋划分为不同的单元来考虑),而预应力的施加是通过给锚索单元一个初始的应变。通过分析得到锚固段剪应力的分布特征,它主要与锚索弹性模量、灌浆体弹性模量、灌浆体半径、锚索半径、灌浆体泊松比这几个参量有关。最后,为了便于工程直接应用,综合以上几方面的影响因素给出压力集中型预应力锚索计算锚固段剪应力的理论公式。

Based on the detailed analysis of the structural character, the mechanics characteristic of a pressure-type anchor is simulated and analyzed by using the finite element software. The concrete and the reinforcing steel are divided into different units and considered with the contingency method in which the initial strain of whole anchor cable is simulated with the prestress. The distribution character of the shear stress along the anchor segment of the partial-cohesive cable is derived. The influence factors of the shear stress distribution are analyzed through the variation of the parameters such as the modulus of elasticity of the anchor cable and the grouted body,the radius of the grouted body and the anchor cable, the Poisson＇s ratio of the grouted body. Finally, the theoretical formula of shear stress distribution along the anchor segment is put forward based on the comprehensive analysis of each influence factor.