深井厚煤层柔模泵注混凝土沿空留巷技术应用研究

发布时间：2019-02-21 18:19

【摘要】：沿空留巷符合安全开采和完全开采的发展方向，具有广阔的应用前景，但已有的研究成果多是建立在浅部薄和中厚煤层沿空留巷的基础上，实践证明深部开采与浅部开采在矿压与显现、瓦斯涌出等方面有很大不同。因此，浅部煤层沿空留巷的理论成果与实践经验难以满足深部煤层沿空留巷的需要。本文采用理论研究和现场工业试验相结合的方法，系统研究了柔模混凝土沿空留巷围岩与支护刚度匹配、深井厚煤层沿空留巷支护、Y型通风与瓦斯防治技术，取得了如下研究成果：（1）首次将柔模泵注混凝土支护技术成功应用于大埋深（820m）、大采高（5.2m）的高地压煤层沿空留巷，实测留巷顶底板最大移近量72mm，两帮最大移近量56mm。（2）将沿空留巷直接顶、巷旁支护和底板简化为具有不同刚度的弹性体，建立了支围系统刚度结构模型，分析了各部分对系统刚度的影响，研究认为：单纯提高巷旁支护刚度对控制围岩变形效果不明显，必须保证直接顶刚度、巷旁支护刚度和底板相匹配。（3）利用相邻工作面开切眼和顺槽实现Y型通风，建立了Y型通风主副进风巷配比和配风量的计算公式，，揭示了采空区“U”型圈漏风通道是上隅角瓦斯超限的根本原因，提出减小采空区漏风和留巷埋管瓦斯抽放相结合的瓦斯综合防治技术。（4）威特克提出的“分离岩块法”沿空留巷计算模型具有原理简单和易操作的特点，但是该方法没有考虑开采深度对沿空留巷围岩压力的影响，所以在深井沿空留巷条件下应用时误差较大。在考虑了开采深度的影响后，修正了“分离岩块法”计算模型，进而提出了修正后的沿空留巷围岩压力计算公式。（5）深井厚煤层开采时矿压显现剧烈，加之试验工作面顶板松软破碎，移架后浇墙区顶板随即垮落，导致沿空留巷难以施工。为了防止浇墙区顶板垮落，提出一种在工作面煤壁附近对留巷浇墙区顶板进行锚网索永久加强支护的新方法；为了及时有效地切断直接顶，阻挡采空区矸石冲入留巷，提出一种在超前架间进行切顶挡矸支护的新工艺。
[Abstract]:The gob-side roadway is in line with the development direction of safe mining and complete mining, and has broad application prospects. However, most of the existing research results are based on the shallow and medium thick coal seams along the gob-side roadway. Practice shows that deep mining and shallow mining are very different in mine pressure, gas emission and so on. Therefore, the theoretical results and practical experience of retaining roadway along goaf in shallow coal seam are difficult to meet the needs of deep coal seam. In this paper, the method of combining theoretical research with field industrial test is used to systematically study the matching of surrounding rock and supporting stiffness of flexible formwork concrete along goaf retaining roadway, deep and thick coal seam gob retaining roadway support, Y-type ventilation and gas prevention technology. The research results are as follows: (1) for the first time, the flexible form pump concrete support technology has been successfully applied to the roadway along the goaf of the high pressure coal seam with large buried depth (820m) and high mining height (5.2m), and the measured maximum movement of the roof and floor of the roadway is 72 mm. The maximum movement of the two sides is 56mmm. (2) the direct roof, side support and floor are simplified as elastic bodies with different stiffness, and the stiffness structure model of the bracing system is established, and the influence of each part on the system stiffness is analyzed. It is considered that simply increasing the stiffness of roadway side support has no obvious effect on controlling the deformation of surrounding rock, so it is necessary to ensure the direct roof stiffness, and the supporting stiffness of roadway side is matched with the bottom slab. (3) Y type ventilation is realized by using the opening and cutting hole of adjacent working face and the following slot. The formula for calculating the ratio and air distribution of the main and secondary air entry roadways of Y-type ventilation is established. It is revealed that the "U" ring air leakage passage in the goaf is the fundamental cause of the gas overrun in the upper corner. This paper puts forward a comprehensive gas prevention and control technology combining the reduction of air leakage in goaf and gas drainage of buried pipe in goaf. (4) the calculation model of separated rock block method for roadway along the goaf proposed by Wittke has the characteristics of simple principle and easy operation. But this method does not consider the influence of mining depth on surrounding rock pressure of gob-side roadway, so the error is large when it is applied in the condition of deep gob-side roadway. After considering the influence of mining depth, the calculation model of "separated rock block method" is revised, and the revised formula for calculating surrounding rock pressure along goaf roadway is put forward. (5) the pressure of deep and thick coal seam appears violently during mining. In addition, the roof of the test working face is soft and broken, and the roof in the area of cast-in-place wall immediately collapses, which makes it difficult to construct the roadway along the gob. In order to prevent roof collapse in cast-in-place wall area, a new method of bolting net and cable permanent strengthening support for roof in cast-in-place wall area of retaining roadway near coal wall is put forward. In order to cut off the direct roof in time and prevent the gangue from rushing into the roadway in goaf, a new technology of cutting the roof and blocking the gangue between the leading frames is put forward.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TD353;TD712

【参考文献】