为了给出定量的围岩稳定性评价方法,将锚杆与围岩的复合体等效为围岩加固体,继而建立了深部围岩与加固体力学分析模型,在求得加固体的物理力学参数表达式后,对模型进行了力学分析,提出依靠加固体变形程度来评价围岩稳定性的方法,最后,结合算例对某巷道围岩进行稳定性分析,同时分析了岩体和锚杆参数对围岩稳定性的影响.研究结果表明:通过理论计算得出的巷道洞壁位移以及锚杆轴力与实测值相近,证明了模型的合理性;锚杆支护设计遵循长而疏、短而密的规律,但锚杆长度增加或间排距减小到一定值后,围岩稳定性的增幅在降低;锚杆预紧力与围岩稳定性呈线性变化规律,锚杆弹性模量与直径对围岩稳定性影响较小;该方法能快速、简洁地分析岩体与锚杆参数对围岩稳定性的影响,也能优化锚杆支护参数.%To propose a quantitative evaluation method for the stability of surrounding rock , the composite of bolt and sur-rounding rock was equivalent to the reinforcement body of surrounding rock , and a mechanical analysis model for the deep surrounding rock and the reinforcement body was established .After obtaining the expressions for the physical and mechanical parameters of the reinforcement body , the mechanical analysis of the model was conducted , and a method for evaluating the stability of surrounding rock by the deformation degree of the reinforcement body was proposed .Finally, the stability of sur-rounding rock in a roadway was analyzed by using this theory combined with the calculation case , and the influence of the rock mass and bolt parameters on the stability of surrounding rock was analyzed .The results showed that the displacement of the cave wall and the axial force of the bolt in the roadway obtained by the theoretical calculation were similar to the measured values , which proved the rationality of the model .The design of bolt support should follow the laws of long and sparse , short and dense , but after the length of the bolt increased or the distance between the rows decreased to a certain value , the in-crease amplitude of the stability of surrounding rock was decreasing .The pre-tightening force of the bolt and the stability of surrounding rock were linearly changing , and the elastic modulus and diameter of the bolt had little effect on the stability of surrounding rock .The method can quickly and concisely analyze the influence of the rock mass and bolt parameters on the stability of surrounding rock , as well as optimizing the parameters of bolt support .
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