回采巷道垂直挤压型底臌机理及控制技术研究

发布时间：2018-05-10 07:14

本文选题：回采巷道 + 垂直挤压型底臌　；参考：《太原理工大学》2017年硕士论文

【摘要】：巷道底臌在煤矿井下是一种常见的地质现象,也是影响煤矿高效、安全生产的关键问题之一。严重的底臌会使巷道断面大大缩小,通风受阻、设备倾翻、行人无法通行,尤其在软岩巷道和动压巷道中,底臌现象更加普遍,底臌程度也更加严重。本文针对义棠煤矿+560m水平10502综采工作面运输巷发生的垂直挤压型底臌现象,采用现场调研、理论分析、室内试验及计算机数值模拟等方法,对回采巷道底臌力学机理及底臌过程进行了深入研究,得出了一些有益结论:(1)软岩巷道中发生底臌的主要影响因素是巷道底板围岩的结构和岩性。其中,底板岩体的赋存结构决定了巷道底臌的类型;底板岩体的岩性决定了巷道底臌的程度(或者底臌量的大小)。(2)回采巷道不同于一般巷道,底臌具有其独特的特征:(1)随着工作面的推进,巷道在距工作面一定距离内周期性发生底臌;(2)在开采引起的超前支承压力作用下,底臌量往往较大,底臌严重;(3)底臌是伴随着巷道开挖掘进到工作面回采整个过程,底臌是持续变化的,具有动态性。(3)回采巷道发生垂直挤压型底臌的根本原因是超前支承压力形成的垂直应力超过了底板破碎岩体的极限承载力。基于土力学中的滑移线场理论,结合弹塑性力学中的刚体极限平衡法,得出了底板围岩的极限承载力,并且预测出底臌量的大小。(4)利用数值模拟软件Flac3D对提出的不同底臌控制方案进行支护效果模拟对比,经分析选用底板注浆+底板锚杆的方案对底臌进行控制,注浆可以将底板破碎岩体重新胶结整合,提高底板岩体的内聚力及内摩擦角,而底板锚杆即可以形成“销钉”作用,切断底板岩体内的塑性滑移线,又可以利用锚索调动深部稳定围岩的承载力,可以达到更好的控制效果。(5)将上述底臌控制方案应用于义棠煤矿10502综采工作面运输巷的底臌治理,并进行长期的现场观测,在实施2个月后,试验段从距工作面130m距离至工作面推过监测点为止,最大底臌量为86mm,符合预期效果,表面控制效果良好,为同类型巷道的底臌治理提供了一些借鉴之处。
[Abstract]:Roadway floor heave is a common geological phenomenon in coal mine, and it is also one of the key problems affecting the high efficiency and safety production of coal mine. Serious floor heave can greatly reduce the section of roadway, block ventilation, overturn equipment, and make pedestrians impassable, especially in soft rock roadway and dynamic pressure roadway, the phenomenon of floor heave is more common and the degree of floor heave is more serious. Aiming at the phenomenon of vertical extrusion floor heave in the transport roadway of 560m level 10502 fully mechanized mining face in Yitang Coal Mine, this paper adopts the methods of field investigation, theoretical analysis, indoor test and computer numerical simulation, etc. The mechanical mechanism of floor heave and the process of floor heave in mining roadway are studied, and some beneficial conclusions are drawn. The main influencing factors of floor heave in soft rock roadway are the structure and lithology of roadway floor surrounding rock. Among them, the occurrence structure of floor rock mass determines the type of floor heave of roadway, and the lithology of floor rock mass determines the degree of floor heave of roadway (or the magnitude of floor heave), which is different from that of general roadway. The floor heave has its unique feature: (1) with the advance of the working face, the floor heave occurs periodically within a certain distance from the working face) under the action of leading support pressure caused by mining, the floor heave is often larger. Floor heave is accompanied by the whole process of roadway excavation to face mining, and the floor heave is continuously changing. The fundamental cause of vertical extrusion floor heave in mining roadway is that the vertical stress formed by leading bearing pressure exceeds the ultimate bearing capacity of broken rock mass. Based on the slip line field theory in soil mechanics and the ultimate equilibrium method of rigid body in elastoplastic mechanics, the ultimate bearing capacity of surrounding rock of bottom plate is obtained. And the magnitude of floor heave is predicted. The numerical simulation software Flac3D is used to simulate and compare the support effect of different floor heave control schemes, and the floor heave is controlled by selecting the floor grouting anchor rod scheme. Grouting can recement the broken rock mass of the floor and improve the cohesion and friction angle of the rock mass, and the anchor rod of the bottom plate can form the action of "pin" and cut off the plastic slip line in the bottom rock. In addition, the anchor cable can be used to mobilize the bearing capacity of deep stable surrounding rock, and better control effect can be achieved. The floor heave control scheme mentioned above can be applied to the floor heave control of 10502 fully-mechanized mining face in Yitang Coal Mine, and long-term field observation is carried out. After 2 months of implementation, the maximum floor heave of the test section is 86mm from 130m away from the working face to the monitoring point of the working face, which is in line with the expected effect, and the surface control effect is good, which provides some references for the treatment of the floor heave of the same type of roadway.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD353

【参考文献】