【作者】 许万忠；

【导师】 彭振斌； 曹平；

【作者基本信息】 中南大学 ， 地质工程， 2006， 博士

【摘要】 随着高陡节理边坡工程的不断涌现，边坡的稳定性问题日趋复杂和重要，锚杆作为常规的边坡加固手段被广泛采用。然而，由结构弱面控制的节理边坡实施锚杆加固措施时，巨大的下滑力常会造成节理滑动面区域锚杆受力状态的劣化；预应力锚杆由于岩石的蠕变及钢筋的塑性，也会导致锚杆预应力的衰减；由于岩体节理力学性质的各向异性，使边坡锚固工程设计时，产生加锚节理面抗剪强度和锚杆抗拔力两者难以兼顾的矛盾；锚杆诸如此类的弊端将会导致工程中锚杆锚固功能的失效，从而给边坡工程的支护安全带来隐患。锚注加固工艺将锚杆和注浆的加固手段有机地结合起来，通过形成锚杆与注浆胶结体复合结构，进而达到有效加固节理边坡的目的，这种特殊的复合加固结构充分发挥了两种材料的特点，因此避免了锚杆单独作用所存在的弊端，使锚注加固后的边坡岩体应力集中现象得以改善，岩体结构的受力状态更趋合理，从而降低了加锚节理边坡的安全隐患。通过研究节理裂隙边坡的锚注加固效应，最终为边坡的锚注加固优化设计提供理论指导，是当前势在必行的工作，作者结合湖南省交通厅“常德一张家界高速公路节理边坡锚注加固效应研究”课题项目，对节理裂隙边坡稳定性及锚注加固效应进行了全面深入的研究。首先，根据节理边坡的基本破坏类型，建立了相应的边坡失稳力学状态模型，运用相应的力学理论，分析了节理弱面对边坡岩体的强度及稳定性的控制作用；基于强度理论和潜在滑移面理论对节理边坡的失稳破坏机制进行了推理和论证。根据节理边坡锚注加固结构的受力特点，建立了锚注节理力学模型，基于岩体节理力学理论，在分析岩体节理、加锚节理的强度特性以及本构关系的基础上，构建了锚注节理的剪切强度公式以及本构方程，通过普通节理、加锚节理和锚注节理三者力学特性的对比，揭示出节理边坡锚注加固效应的力学本质。利用RYL-600型微机控制岩石剪切试验机，通过室内模拟节理剪切试验的方法，研究了各种结构状态节理面的剪切力学特性，获得了相应的剪力—剪位移全程曲线，经过对试验结果的整理、分析和对比，得到了锚注节理的强度和变形规律及其相应的影响因素，揭示了锚注节理相对于普通节理、加锚节理的力学特性的变化规律。应用FLAC3D数值分析软件，对锚注加固节理边坡进行了模拟对比分析，通过对开挖节理边坡、注浆节理边坡、加锚节理边坡以及锚注节理边坡的应力场、位移场和特征测试点应力应变的分析，从宏观的角度说明了锚注加固对于节理裂隙边坡强度及稳定性的贡献。运用断裂力学和损伤力学分别对锚杆的加固效应及岩体注浆的加固效应进行了研究；并对锚固工程中锚杆单独作用的弊端和不足进行了分析。本文所做的研究工作，立足于学科前沿，作者充分认识到岩土工程是一门交叉性很强的边缘学科特点，广泛运用最新的力学理论、先进的试验手段以及数值分析方法，对节理裂隙边坡的稳定性及锚注加固效应进行了研究，该项目的研究对于揭示节理边坡锚注加固机理以及锚注加固工程的优化设计具有理论和现实意义。更多还原

【Abstract】 In resent years, there are more and more large-scale jointed slopeprojects. It becomes more and more complex and important in field ofslope stability. Rock bolt is widely used in slope reinforcement as aregular reinforcement method. When slope reinforced by rock bolt, thestress state of rock bolt in the area of slip plane will become bad becauseof great slippage force. The prestressed rock bolt will lose its stress withcreep of rock and plasticity of reinforcing steel bar. In slopereinforcement design, the anisotropic characteristic of rock mass will leadto contradiction that the shear resistance strength of jointed reinforced byrock bolt and pull-out resistant force can not exert at the same time. Thedisadvantages of rock bolt will lead to the invalidation of reinforcementcharacteristic, which will bring hidden troubles in the slope stability. Thecraft of bolting and grouting combine the advantages of bolting andgrouting. It makes the composite structure with bolt and grouted material.The craft exert the advantage of bolting and grouting separately in thereinforcement of slope, which avoids the disadvantages of bolt andavoids the phenomenon of stress concentration. The reinforcementmethod of bolting and grouting makes the stress state in rock mass morereasonable, and avoid the hidden troubles in slope stability. It isimportant to study the effect of bolting and grouting reinforcement inslope is studied so as to provide the guidance for the optimum design ofslope reinforcement method. The scientific research of HuNancommunications ministry with title of’Study of bolting and grouting inrock jointed slope of ChangDe-ZhangJiajie speedway’is chosen as thestudy background, the stability of rock jointed slope and effect of boltingand grouting are studied.First of all, the mechanical model of slope stability is foundedaccording to the failure characteristic of rock jointed slope. According tomechanical theory, the effect of weakness plane to the strength andstability of slope is studied. The reason of failure in jointed slope isanalyzed according to the strength theory and potential slip plane theory.According to the mechanical characteristic of slope with the reinforcement of bolting and grouting, the mechanical models arefounded for the reinforcement of bolting and grouting. According thetheory of jointed mechanic in rock mass, and take into consideration ofthe characteristic of rock joint, bolting and grouting strengthcharacteristic and constitutive relation, the shear strength of bolting andgrouting joint is deducted. By the compare analysis of characteristic forregular joint, bolting joint, bolting and grouting joint, the mechanicalcharacteristic for the effect of bolting and grouting in reinforcementmethod of joint slope.By the RYL-600 rock shear test machine, the shear experiment ofrock sample is done. The shear characteristic of joint plane for differenttype of structural state is studied. Different curves are obtained to analyzethe characteristic of stress-strain. By the result of analysis, the effectfactor and the characteristic of strength and deformation of joint with thereinforcement of bolting and grouting are obtained. It is different inmechanical characteristic of joint between regular joint and joint withbolting and grouting reinforcement.By using the numerical analysis software FLAC3D, jointed slopeswith bolting and grouting reinforcement are studied. The analysis is donein the field of stress, displacement and the characteristic of monitoringpoints. The numerical simulation models consist of jointed slope with thereinforcement of bolting, grouting, bolting and grouting. The effect of thereinforcement to the jointed slope is studied.According to the theory of fracture mechanics and damagemechanics, the effect of bolting and grouting to the jointed slope arestudied. The disadvantages of rock bolt when it exerts alone are studied.The latest mechanical theories, the advanced experiment methods andnumerical simulation methods are adopted in this paper to study tostability of jointed rock slope and the effect of bolting and groutingreinforcement. The research work in this paper can open up themechanism of combined supporting in jointed slope and provide thetheoritical and practical meaning for the optimum design.更多还原