南水北调工程采空区注浆数值模拟研究

发布时间：2018-02-08 22:02

本文关键词： 注浆宾汉姆浆液非稳态k-紊流模型采空区南水北调　出处：《天津大学》2014年硕士论文　论文类型：学位论文

【摘要】：南水北调中线工程穿越多个煤矿采空区，对工程的安全施工与运行造成了严重威胁，因此，对煤矿采空区进行注浆加固处理已成为工程迫切需要解决的问题。注浆技术已被广泛地应用于地基工程、桩基工程、边坡工程、隧道工程和煤矿开采，由于注浆具有掩蔽性和岩石地层的复杂性，数值模拟技术比传统试验方法具有更大的灵活性、经济性，已经广泛应用到注浆工程中。目前关于注浆数值模拟的研究主要是针对单一裂隙或者单个的注浆孔，这与实际注浆工程中复杂交错布置的裂隙情况或者大面积的多孔注浆情况差别较大，且没有考虑各裂隙或者注浆孔之间流体的相互影响，而且绝大多数的研究将浆液流态近似做层流处理，选用渗流控制模型，，这与实际情况下浆液的紊流状态不符。因此，研究三维多序孔紊流非稳态注浆对确保南水北调渠道长期安全稳定运行具有重要的理论意义和实践价值。首先，在国内外研究的基础上，基于耦合多种地质信息的三维几何模型，建立了非稳态三维宾汉姆流体k紊流注浆数学模型，采用贴体网格划分技术，建立注浆网格物理模型，根据注浆工程中地质层的地质参数，采用不同的孔隙率和阻力系数，对宾汉姆流体浆液在采空区中的紊流扩散进行了模拟，实现了宾汉姆流体浆液的采空区多孔分序注浆模拟。其次，结合南水北调中线工程某煤矿采空区对宾汉姆流体浆液在采空区中的紊流扩散规律进行了模拟，分析了浆液扩散、渗透的变化规律，并将模拟结果与理论分析结果、实际工程数据进行对比，验证了模型的可靠性。最后，对0.5Mpa、1.0Mpa、1.5Mpa三种注浆压力条件下的注浆效果进行了对比分析。模拟结果表明： (1)由于重力和注浆压力的双重作用，浆液在采空区中的扩散分布呈现倒漏斗形状； (2)I、II序孔注浆时，浆液的扩散半径随着时间的增加而逐渐变大，但其变化率随着时间的增加而逐渐减少，最后趋于零； (3)I、II序孔注浆时，浆液的充填率随着时间的增加而逐渐变大，但其变化率随着时间的增加而逐渐减少，最后趋于零。
[Abstract]:The project of the middle route of the South-to-North Water transfer Project passes through many coal mine goaf areas, which poses a serious threat to the safe construction and operation of the project, so, Grouting technology has been widely used in foundation engineering, pile foundation engineering, slope engineering, tunnel engineering and coal mining. Due to the masking property of grouting and the complexity of lithostratigraphy, numerical simulation technology is more flexible and economical than the traditional test method, so it has been widely used in grouting engineering. At present, the research on numerical simulation of grouting is mainly aimed at a single fissure or a single grouting hole, which is quite different from the situation of complex interlaced cracks or large areas of porous grouting in actual grouting engineering. Moreover, the interaction of fluid between different cracks or grouting holes is not considered, and most of the studies make the slurry flow state approximate laminar flow treatment and select the seepage control model, which is not consistent with the actual turbulent state of the slurry. It is of great theoretical significance and practical value to study the unsteady grouting of three-dimensional multi-sequence hole turbulent flow in order to ensure the long-term safe and stable operation of the channel of South-to-North Water transfer. First of all, on the basis of domestic and foreign research, based on the 3D geometric model coupled with various geological information, a mathematical model of unsteady 3D Bingham fluid k turbulent grouting is established, and the body-fitted meshing technique is adopted. Based on the geological parameters of geological layer in grouting engineering, the turbulent diffusion of Bingham fluid slurry in goaf is simulated by using different porosity and resistance coefficient. The simulation of Bingham fluid slurry injection in goaf is realized. Secondly, the turbulent diffusion law of Bingham fluid slurry in goaf is simulated by combining with the goaf of a coal mine in the middle route of South-to-North Water transfer Project, and the slurry diffusion is analyzed. The variation law of infiltration is compared with the theoretical analysis and the actual engineering data to verify the reliability of the model. Finally, the grouting effect under three grouting pressures of 0.5Mpa-1.0Mpa-1.5Mpa is compared and analyzed. The simulation results show that:. (1) due to the double action of gravity and grouting pressure, the distribution of slurry in goaf is in the shape of inverted funnel; The diffusion radius of the slurry increases with the increase of time, but the rate of change decreases with the increase of time, and finally tends to zero. The filling rate of the slurry increases with the increase of time, but the change rate decreases with the increase of time, and tends to be zero.
【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV68;TV543

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