【作者】 张益东；

【导师】 屠世浩；

【作者基本信息】 中国矿业大学 ， 采矿工程， 2013， 博士

【摘要】 锚杆支护不仅可以起到悬吊、组合梁和挤压加固的作用，而且能够与围岩相互作用形成具有一定强度的承载结构，然而现行锚杆支护设计缺乏对承载结构的考虑。本文在前人研究的基础上，采用实验室岩块实验、平面应变相似模拟试验、数值模拟、理论分析、计算机编程和工程实践相结合的综合研究手段，提出了“锚固复合承载体”的概念，建立了不同巷道断面的锚固复合承载体力学模型，揭示了锚固复合承载体的承载机理和承载特性，确定了锚固复合承载体稳定性判据，并根据判据开发锚杆支护参数设计软件。论文主要成果如下：（1）锚固复合承载体内部的应力及巷道围岩移近量的变化呈如下规律：在加载初期，其应力与位移缓慢增长；加载中期，随着锚杆与围岩的协调作用，其应力快速增长至围岩的承载的峰值应力，锚固复合承载体很快产生承载作用，巷道位移也随之增长；外载达到一定程度后，锚固复合承载体内的应力超过其极限承载能力，围岩发生破坏致应力迅速降低至残余承载应力状态，而此时巷道变形量大幅度增加。（2）提出了“锚固复合承载体”的概念。反映锚固复合承载体在外载作用下抵抗变形能力的标志之一是巷道围岩移近增速，巷道围岩移近增速愈小，巷道抵抗变形的能力愈大。模拟研究表明，巷道围岩移近增速的变化呈如下规律：峰前承载阶段小于峰后阶段，高密度锚杆支护小于低密度支护；长锚杆支护小于短锚杆支护；大直径锚杆支护小于小直径锚杆支护。但当锚杆长度的增加到一定值后对锚固复合承载体的承载能力提高作用较小。（3）基于半圆拱巷道和矩形巷道，建立相应的锚固复合承载体的力学模型，并计算锚固复合承载体的几何参数和强度。基于自然平衡拱理论计算了上覆潜在松动岩层的重量，提出了锚固复合承载体的稳定性判据。（4）通过对锚固复合承载体进行的破坏性加载试验，得出锚固复合承载体的破坏形式：顶板发生近似“人”字形的裂缝后，顶板下沉量急剧增加，加载载荷难以维持稳定。通过对锚固复合承载体强度实测验证了理论计算的正确性。（5）根据锚固复合承载体稳定性判据建立了锚杆支护参数设计步骤，并初步编写了巷道锚杆支护参数设计软件。针对三个不同巷道的生产地质条件，采用巷道锚杆支护参数设计软件进行支护参数设计，并将设计结果应用于工程实践，结果表明基于“锚固复合承载体”理论的参数设计应用后有效的控制了巷道变形，从工程实践的角度验证了本文研究成果的科学性和可靠性。更多还原

【Abstract】 Bolting support can not only play a role as suspension, composite beam andcombined arch, but also form a bearing structure with some intensity by theinteraction with the surrounding rock. But the current bolting design methods don’ttake the bearing structure into account. Based on the analysis of predecessors’achievements and by combining with the existing theoretical results of surroundingrock control, plane strain similar material simulation experiment, numericalsimulation analysis, theory analysis, calculator program and engineering practices,this dissertation put forward the theory of Composite Bolt-Rock Bearing Structure,established a mechanical model of Composite Bolt-Rock Bearing Structure ofdifferent roadway section, revealed its loading bearing mechanism and characteristic,determined its stability criterion and developed a design software. Main results are asfollows:(1) The change of stress and rock deformation around roadway of CompositeBolt-Rock Bearing Structure were as follows: In the initial stage the stress anddeformation increased slowly. In the middle stage the stress had a rapid growth topeak stress and the deformation increased rapidly with the coordinated effect of boltand surrounding rock. When the load reaches a certain degree, the stress exceeded thelimit bearing capacity and then fallen to the residual stress state due to the damage ofsurrounding rock and the deformation was accelerated development.(2) The paper put forward the concept of Composite Bolt-Rock Bearing Structure.Displacement per stress of rock deformation around roadway was one symble whichreflected the ability to resist deformation under pressure. The less displacement perstress of rock deformation around roadway was, the stronger the ability to resistdeformation of the roadway had. The simulation showed that the displacement perstress in the initial and middle stage was less than it is in the last stage, thedisplacement per stress with high support density was less than it is with low supportdensity and the displacement per stress with long bolt length was less than it is withshort bolt length. The displacement per stress with large bolt diameter was less than itis with small bolt diameter. However, when the bolt length was relatively long,increasing the bolt length had little effect on the strength of Composite Bolt-RockBearing Structure. (3) Based on different roadway section, for instance semi-circular arch andrectangle, we established a corresponding mechanical model of Composite Bolt-RockBearing Structure and obtained the formula of geometric parameter and strength. Theformula of Composite Bolt-Rock Bearing Structure strength indicated that thestrength not only associated with force condition, but also affected by geometricparameter. Based on natural equilibrium arch theory, we calculated the weight of thepotential overlying loose strata and determined stability criterion of CompositeBolt-Rock Bearing Structure.(4) By separating Composite Bolt-Rock Bearing Structure from surrounding rockand its destructive loading test, we got its destruction form of Composite Bolt-RockBearing Structure: cracks occurred in roof, roof sag increased dramatically andapplied stress was difficult to maintain stable. The correctness of the theoreticalcalculations was verified.(5) Based on the stability criterion of Composite Bolt-Rock Bearing Structure,we established design procedure of bolt support parameters initially and developeddesign software of roadway bolting support with a computer program. The resultsdesigned by this design software were applied successfully in three field tests ofGucheng coal mine, Dan Shuigou coal mine and Huale coal mine under typicalgeological conditions of roadway. The application results showed that the bolt supportparameters designed based on Composite Bolt-Rock Bearing Structure controlled ofthe deformation of roadway effectively and the research results of paper werevertifyed to be sicence and reliability from the engineering practice.更多还原