沿空留巷围岩注浆数值模拟与合理注浆时机研究

发布时间：2018-06-15 16:20

本文选题：沿空留巷 + 注浆方法　；参考：《山东科技大学》2017年硕士论文

【摘要】：沿空留巷巷道围岩长期处于高支承压力状态,极易发生大变形和失稳。单一的锚杆支护已不能满足工程正常生产的要求。现场工程实践经验表明,锚、注联合支护对巷道围岩支护效果比较好,然而注浆时机的选择对注浆效果影响很大,决定着注浆工程甚至沿空留巷的成功与否。本文采用理论分析、数值模拟研究相结合的方法,对动态数值模拟注浆方法和沿空留巷围岩合理注浆时机进行了研究。主要研究工作包括以下方面。基于已有研究成果,分析了沿空留巷巷道围岩上的应力演化过程及锚杆支护作用失效的原因,分析了注浆对围岩及锚杆支护作用的补强作用;确定了注浆围岩加固参数及可注浆范围的判定依据。通过运用FLAC3D数值模拟软件内置的应变软化本构模型和FISH语言构建了动态注浆数值模拟方法,能够自动根据塑性应变率大小确定可注浆范围煤岩体注浆后强度提高幅度大小。通过数值模拟,得到了注浆前沿空留巷巷道煤帮破碎区宽度、锚杆支护前后变形量差值、可注浆区域内围岩的体应变量、孔隙率、渗透系数的平均值在工作面采动影响下的变化规律:随工作面推进,可注浆区域内围岩的平均体应变量、孔隙率、渗透系数的平均值变化呈现出先增大后减小的趋势,在滞后工作面10m位置处达到峰值;煤帮破碎区宽度在工作面后方10mm位置也达到了锚杆支护范围的边缘。因此,将滞后工作面10m作为沿空留巷煤帮合理的注浆时机。最后,运用数值模拟得到的不同注浆位置注浆后该位置的最终位移量进行了验证。并且进一步对距工作面不同位置的顶板进行了注浆数值模拟研究,通过分析比较各个注浆时机围岩稳定后的最终下沉量的大小,确定了沿空留巷巷道顶板的合理注浆时机为超前工作面10m。
[Abstract]:The surrounding rock of roadway along goaf roadway is in the state of high supporting pressure for a long time, so it is easy to occur large deformation and instability. Single bolt support can not meet the requirements of engineering normal production. Field engineering experience shows that anchor and grouting combined support have better support effect on surrounding rock of roadway, but the choice of grouting timing has a great influence on grouting effect, which determines the success of grouting project and even the roadway along goaf. In this paper, the dynamic numerical simulation grouting method and the reasonable grouting timing of surrounding rock along goaf are studied by combining theoretical analysis and numerical simulation. The main research work includes the following aspects. Based on the existing research results, the stress evolution process of roadway surrounding rock along goaf and the reason of failure of bolting action are analyzed, and the reinforcement effect of grouting on surrounding rock and bolting support is analyzed. The parameters of grouting surrounding rock and the range of grouting are determined. By using the strain softening constitutive model built in the FLAC3D numerical simulation software and the fish language, the dynamic grouting numerical simulation method is constructed, which can automatically determine the extent of strength increase of coal and rock mass after grouting according to the plastic strain rate. Through numerical simulation, the width of coal side broken area, the difference of deformation before and after bolting support, the body strain and porosity of surrounding rock in grouting area are obtained. The law of change of average permeability coefficient under the influence of mining movement: with the advance of working face, the average body strain, porosity and permeability coefficient of surrounding rock in grouting area show the trend of increasing first and then decreasing. The peak value is reached at the 10m position of the delayed working face, and the width of the broken area of the coal side reaches the edge of the bolting support range at the 10mm position behind the working face. Therefore, the 10 m lag face is regarded as the reasonable grouting time for the coal side along the gob retaining roadway. Finally, the final displacement of different grouting locations is verified by numerical simulation. Furthermore, the numerical simulation of grouting is carried out on the roof at different positions from the working face, and the final subsidence of the surrounding rock after each grouting opportunity is analyzed and compared. The reasonable grouting time of roadway roof along goaf is determined to be 10 m ahead of working face.
【学位授予单位】：山东科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD353

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