全长注浆锚杆锚固段剪应力分布特征试验研究

通过WES-50B型万能材料试验机对分别模拟高、中、低三种强度围岩介质的锚杆模型进行了拉拔试验。结果表明,锚杆锚固段的轴应变及第一、第二交界面的粘结应力分布按照负指数规律衰减。根据模型试验所得锚杆体轴应变试验结果,在一定简化假设的基础上,推导了以锚杆为代表的锚固结构轴力及第一、第二界面剪应力分布公式,分析了锚固结构在均匀介质中内锚固段应力、轴力及交界面的剪应力传递、衰减规律,探讨了拉拔力及介质强度对锚固段剪应力的影响。本文的研究为通过模型试验分析以锚杆为代表的锚固结构第一、第二界面剪应力分布提供了参考。

Experimental Study of Shear Stress Distribution in Internal Anchoring Section of a Full-length Grouting Anchor

Drawing experiment of anchor model in simulated surrounding rock medium with high, medium and low intensity was carried out respectively by using universal test machine WES-50B. Results indicate that the distribution of axial strain in anchoring section and bond stress at the first and second interface decays in accordance with the law of negative index. Based on model experimental results of anchor body axial strain and certain simplifying assumptions, formulae about axis force of anchoring structure and shear stress distribution at the first and second interface were derived. The stress in internal anchoring section, the axial force and the shear stress transfer and attenuation in homogeneous medium were analyzed. Above results may provide a reference for experimental analysis of shear stress distribution at the first and second interface of anchoring section.