基于岩体结构效应的顺层边坡锚固机理与失效准则

Fully grouted bolts, due to its proved efficacy and low cost, are widely used to restrain deformation of rock masses and to support the stability of slopes. However, althouth applications of blots have been performed for a long time, the bolting theory and the design method fail to take into account rock mass structural characteritics ant the interaction between the rock mass and the bolt, especially for bolts installed in bedding slopes. Based on the theory of structure controlling stability of slopes and considering the interaction between the rock mass and the bolt,bolting tests, theoretical analysis, numerical modelling and engineering application are adopted to study the reinforcing mechanisms of fully grouted bolts in bedding slopes. The aim of this research is to reveal the interaction behavior between the rock mass, and the bolt and to make clear the deformation mechanism of the bolt subjected to lateral loads. The relationship between the axial floce and the lateral shear force will be discussed and a formulation for calculationg the contribution of the blot to the stability of bedding slopes will be developed. Then, a mechanical analytical model of the bolt in the plastic state will be put forward and a failure criteria of bolting, used for engineering design with enough safety margin, will be found. Finally, a body of theory and a new design method for bolting in bedding slopes, reflecting the structural characteristic of rock masses, will be developed. This investigation focuses on an advanced subject in the field of slope engineering which has rarely been studied. The results obtained through this project will be greatly useful for theory research and engineering practice in rock engineering including open mining, highway and highspeed rail, hydropower engineering and slope engineering, etc., and will have an important value for expansion and application.

针对现行边坡锚固理论与设计方法不考虑岩体结构特征及岩体与锚固结构相互作用机理的理论缺陷问题，基于结构控制稳定的观点，考虑岩体与锚固结构的相互作用，通过边坡岩体锚固模型试验，结合理论分析、数值模拟和工程应用研究，探讨拉剪作用下顺层边坡锚固力学机理；揭示岩体与锚固结构相互作用的内在规律及横向抗剪作用对锚杆受力与变形的影响机制；建立弹塑性状态下锚杆轴力与横向抗力之间的数学力学模型和顺层边坡锚固力计算模型；在此基础上提出锚杆破坏的弹塑性力学模型和考虑安全储备的顺层边坡锚固失效准则；最终提出基于岩体结构效应的顺层边坡锚固理论体系和工程设计方法。本项目的研究内容是当前边坡工程领域的前沿课题，对发展和完善边坡工程锚固理论和设计方法具有重大的理论和工程意义。其研究成果将为我国矿山露天开采、公路、铁路、水利水电等基本建设中边坡工程锚固理论研究与工程实践提供理论支持和解决方法，具有重要的应用推广价值。

针对现行边坡、地下硐室锚固理论与设计方法不考虑岩体的结构特征及围岩体与锚固结构相互作用的理论缺陷问题。本研究在对工程失效案例充分调研的基础上，开展了岩体与锚固结构相互作用机理的试验研究及锚固参数分析，分析了节理岩体锚杆内力演化及变形特征机理。并考虑岩体结构效应的顺层岩层锚杆加固机制及失效模式，在此基础上，建立弹性及塑性大变形状态下节理岩体锚杆锚固力学分析模型及锚固力计算模型，最后提出了考虑横向抗剪效应的顺层岩层锚固设计方法。本研究从结构控制稳定的角度出发，系统地分析了节理岩体锚固理论研究的工程背景和科学意义，探讨了拉剪作用下节理锚杆的力学与变形演化规律，揭示了基于岩石/浆体与锚杆相互作用的节理岩体内在锚固机理。本项目的研究成果将为矿山露天开采、公路、铁路、水利水电等基本建设中边坡工程锚固理论、地下工程支护理论的研究与工程实践提供理论指导，具有重要的应用推广价值。