基于锚杆锚固长度受力全过程力学机理的计算模型研究

Study on the calculation model of the whole process mechanical mechanism based on the anchorage length of bolt

在分析锚杆锚固体上剪应力变化基础上,发现锚杆荷载—变形特性与锚固体表面剪应力建立、局部破坏滑移、剪应力消失过程相关。在Mindlin解得到的锚固体上应力分布模型和荷载-位移指数衰减模型的基础上,建立了锚杆受力全过程计算模型。这种模型与锚杆锚固长度相关,能够将锚杆荷载—位移曲线与锚固体表面剪应力变化对应起来。模型分析表明:锚固长度对锚杆的延性作用很大;锚杆荷载—变形曲线不同形态与锚固长度有关。此外,还提出了锚固体表面局部剪应力达到破坏强度时,有效锚固长度的计算方法。

Founding on the analysis of shear stress changes on the anchorage bolt,Finding bolt load-deformation characteristics is concerned with anchoring surface shear stress created,partial destruction of the sliped,and process of the shear stress disappeared.Based on the stress distribution on the anchoring body model and load-displacement exponential decay model which is obtained from the Mindlin solution,Establish the whole process of anchor force calculation model.The model is concerned with bolt the length of anchor,which is able to correspond bolt load-displacement curve and the change of anchoring surface shear stress.The established analysis model is showed that bolt the length of anchor great effect on bolt ductility action and bolt load-deformation different characteristics.Besides,Also propose effective length of anchor calculation method when anchoring surface local shear stress reach the breaking strength.