基于COMSOL Multiphysics的断层带注浆数值模拟研究

发布时间：2018-04-11 06:47

本文选题：断层注浆 + 管道-裂隙双重介质　；参考：《安徽理工大学》2017年硕士论文

【摘要】：断层不仅使得矿井水文地质条件复杂化,还会降低工程岩体的稳定性,是矿井突水的主要诱发因素之一。另外,断层破碎带往往成为地下水的赋存区间和运移通道。张集煤矿Fs866为西二采区边界断层,落差25～60m,延展长度2412m,对A组煤1413A首采工作面的安全回采构成严重威胁。为保证工作面的安全回采,在分析A组煤开采水文工程地质条件的基础上,对Fs866断层带进行注浆改造。为验证断层注浆的效果,本文将注浆对象(断层破碎带及影响带)视为"管道-裂隙"双重介质,建立了断层注浆水文地质概念模型;采用多场耦合的方法将注浆实际中存在的动水条件、高地应力、裂隙和孔隙水压、注浆压力等要素综合考虑在内。应用Comsol Multiphysics软件被利用于模拟浆液的运移扩散规律,并从浆液渗透的动态过程、浆液扩散断面、单注浆孔浆液扩散半径和裂隙流体平均密度变化四个方面对模拟结果进行分析。另外,论文从钻孔水量、水温、水压的变化,吸水率、物探成果、P-Q曲线分析和钻孔取芯检查等实际指标出发,利用多元信息拟合对注浆效果进行了综合评价。研究结果表明:(1)研究对象Fs866断层带具有一定的含、导水性,为了避免开采扰动引起断层"活化"对Fs866断层带进行注浆加固,最终在断层带形成注浆帷幕,达到堵水加固效果。(2)浆液以注浆孔为中心呈近似圆环状分布,扩散半径与时间呈正相关,而扩散速度在逐渐减小,并最终趋于零。(3)断层影响带的浆液扩散范围处于断层破碎带和完整岩层之间,且裂隙发育程度越大,浆液受到的渗流阻力越小,扩散速度越大,扩散的范围也越大。经分析,模拟扩散半径与理论计算误差控制在10%左右,结果基本吻合。(4)对断层带注浆效果的单因素和多因素的综合分析,显示注浆效果良好,达到堵水加固目的,再次验证了数值模拟结论的正确性。为今后类似注浆工程提供了科学指导。
[Abstract]:Fault not only complicates the hydrogeological conditions, but also reduces the stability of engineering rock mass, which is one of the main inducing factors of mine water inrush.In addition, fault fracture zone is often used as the storage zone and migration channel of groundwater.The Fs866 of Zhangji Coal Mine is a boundary fault in the west second mining area with a drop of 2560 m and an extension length of 2412 m.This poses a serious threat to the safe mining of 1413A first mining face of Group A.In order to ensure the safe mining of coal face, the grouting reformation of Fs866 fault zone is carried out on the basis of analyzing hydrogeological conditions of group A coal mining.In order to verify the effect of fault grouting, the grouting object (fault fracture zone and influence zone) is regarded as "pipe-fissure" dual medium in this paper, and the hydrogeological conceptual model of fault grouting is established.The dynamic water condition, high ground stress, fracture and pore water pressure, grouting pressure and so on are taken into account by multi-field coupling method.Comsol Multiphysics software is used to simulate the migration and diffusion law of slurry. The simulation results are analyzed from four aspects: the dynamic process of slurry permeation, the slurry diffusion section, the dispersion radius of single grouting hole and the average density of fractured fluid.In addition, based on the actual indexes of water quantity, water temperature, water pressure, water absorption, P-Q curve analysis of geophysical exploration results and coring inspection of boreholes, the grouting effect is comprehensively evaluated by multivariate information fitting.The results show that the Fs866 fault zone has a certain content and water conductivity. In order to avoid the fault "activation" caused by mining disturbance, the Fs866 fault zone is reinforced by grouting, and finally grouting curtain is formed in the fault zone.To reach the effect of water plugging and reinforcement.) the grouting fluid has a circular distribution centered on the grouting hole, the diffusion radius is positively correlated with time, and the diffusion velocity is gradually decreasing.Finally, the range of slurry diffusion in the zone affected by fault is between the fault fracture zone and the whole rock layer, and the greater the degree of fracture development, the smaller the seepage resistance of the slurry, the greater the diffusion velocity and the wider the diffusion range.Through the analysis, the simulated diffusion radius and the theoretical calculation error are controlled at about 10%, and the results basically agree with each other. The comprehensive analysis of single factor and multiple factors of grouting effect in fault zone shows that the grouting effect is good, and the purpose of water plugging and strengthening is achieved.The correctness of the numerical simulation results is verified again.It provides scientific guidance for similar grouting projects in the future.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD745.2

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