考虑界面软化特性的土层锚杆拉拔受力分析

郭锐剑^{1, 2}，谌文武^{1, 2}，段建^{1, 2}，言志信^1,2

(1. 兰州大学 西部灾害与环境力学教育部重点实验室，甘肃 兰州，730000；
2. 兰州大学 土木工程与力学学院，甘肃 兰州，730000)

摘 要：基于界面黏结-软化-滑动力学本构模型假定，推导土层锚杆锚固力学微分方程及其解析解。在不同拉拔荷载作用下，锚杆剪应力分布模式大体有3种类型：弹性型、弹性-软化型和弹性-软化-松动型，对一具体的工程问题，这3种模式并非均出现，受材料物理力学性质制约，为此，分析锚杆剪应力分布类型、拉拔极限荷载大小及破坏特征之间的内在关系，并给出相关判别标准及取值方法。同时，还结合已有锚杆拉拔试验资料，通过计算对比分析，验证了该方法的可行性。

关键词：锚固工程；界面力学本构模型；锚杆拉拔极限荷载

Pullout mechanical analysis of soil anchor based on softening behavior of interface

GUO Rui-jian^{1, 2}, CHEN Wen-wu^{1, 2}, DUAN Jian^{1, 2}, YAN Zhi-xin^{1, 2}

(1. Key Laboratory of Mechanics on Disaster and Environment in Western China,
Ministry of Education, Lanzhou University, Lanzhou 730000, China;
2. School of Civil Engineering and Mechanics, Lanzhou University, Lanzhou 730000, China)

Abstract:Based on interface stick-soft-slip constitutive model presumption, the differential equation of soil anchorage mechanics and analytic solutions were presented. Under different pullout loadings, distribution pattern of anchor shear stress have three types, i.e. elasticity, elasticity-soften, and elasticity-soften-slip, but the three types do not all appear, to an anchorage engineering, and are restricted by physical and mechanical properties of materials. So, the internal relations among distribution pattern of anchor shear stress, ultimate pullout loading and destructive characteristics are analyzed, and discriminant criterions and ascertain methods are presented. At the same time, with the anchor pullout test data, the feasibility of method is verified by calculation and contrastive analysis.

Key words:anchorage engineering; interface mechanical constitutive model; ultimate pullout loading of anchor