弱胶结覆岩高强度开采岩层与地表移动规律研究

发布时间：2018-04-16 19:15

本文选题：弱胶结覆岩高强度开采 + 现场实测　；参考：《中国矿业大学》2017年硕士论文

【摘要】：本文以营盘壕煤矿2201工作面地质采矿条件为依托原型,采用实测数据分析、数值模拟实验与相似材料模拟实验相结合的方法,对弱胶结覆岩高强度开采下的地表与岩层移动变形规律进行了研究,取得的主要研究成果如下:1)对营盘壕矿区岩层进行实地取样并进行力学实验,实验表明90%的岩层抗压强度均低于30MP,且岩层结构均以泥质胶结为主,具有胶结性差、易风化、对扰动敏感等物理特性,故确定了营盘壕矿区上覆岩层均属于弱胶结性岩层。2)根据现场实测数据绘制出了地表移动变形曲线图,揭示了弱胶结覆岩地表动态移动变形的变化规律;并进一步详细对比分析了营盘壕煤矿与临近的小纪汗煤矿的地质采矿参数与岩层结构,采用类比法确定了营盘壕煤矿2201工作面地表预计参数大小。3)采用数值模拟实验研究了一次性采全高与分层开采两种开采方式下的地表与覆岩移动变形规律以及覆岩内部应力场、塑性区变化规律,揭示了在弱胶结覆岩地层条件下更适合一次性采全高的开采方式,为2201工作面实际开采时提供了理论支撑。4)将理论分析与相似材料模拟实验结果相结合,得出了直接顶应力随着距离开切眼距离的不同而呈现不同类型函数的变化规律;且在高围压状态下,弱胶结覆岩由于自身物理性质而易产生假塑性弯曲,这些“假塑性体”内部产生了与正应力呈不同角度的裂隙,依然可以看成为两端固定,中间悬空的“简支梁”平衡结构;对于地表移动变形而言,下沉曲线收敛速度较一般地质采矿条件下的地表下沉曲线收敛速度慢,且下沉值偏小。5)以弱胶结覆岩岩层动态移动过程为研究基础,建立了弱胶结覆岩开采岩层移动力学模型。并以该力学模型为理论依据,结合材料力学相关知识,推导出了新的弱胶结覆岩开采垮落带发育高度的预测方法。6)理论分析了弱胶结覆岩地表下沉系数远远小于我国东部软岩条件下开采的经验下沉系数的四个因素。三个次要因素:弱胶结覆岩水化膨胀因素、似“覆岩离层注浆”因素、冲洪积砂的流动性因素;一个主要因素:岩层的巨厚特性因素。岩层巨厚的特点使得其在岩层移动变形向地表传递的过程中形成了类似于东部煤矿坚硬岩层的抗变形的作用。
[Abstract]:Based on the conditions of Ying Hao coal mine 2201 working face of geological and mining based on the prototype, using data analysis, numerical simulation and similar material simulation method combining experiment, studied the deformation regularity of weakly cemented rock high intensity mining under surface and strata movement, the main research achievements are as follows: 1) field samples of rock and mining camp trench mechanics experiment, experiment shows that rock compressive strength of 90% is lower than that of 30MP, and all strata structure by clay cementation. With poor cementation, easy weathering, sensitive to disturbance and other physical properties, so to determine the Ying Hao strata belong to the mining area of the rock cemented.2) according to the measured data to draw out the surface movement and deformation curves, reveal the regularity of weakly cemented rock dynamic surface movement and deformation; and further detailed comparative analysis of the coal mine and camp Hao Lin Geological parameters and rock structure near Xiaojihan coal mine, by analogy to determine the surface Ying Hao coal mine 2201 working face prediction parameters of size.3) was studied by one-time mining surface and overburden mobile high slice mining and two kinds of mining methods and the deformation of overburden internal stress field numerical the plastic zone change rules, revealed in the overburden strata under the condition of weak cementation is more suitable for disposable fully mechanized mining method, provides a theoretical support for the practice of 2201 working face.4 mining) combining the theoretical analysis with the similar material simulation experiment results have been obtained directly with the distance from the left top stress cut from different types of functions; and in high confining pressure, weak cementation of overlying rock due to its physical properties and is easy to produce fake plastic bending, these "fake plastic body and is internally generated The stress in different angle fracture, still can be seen as fixed at both ends of intermediate "hanging beam" balance structure; for surface deformation, surface subsidence curve convergence rate than the general conditions of Geology and mining subsidence curve of slow convergence and subsidence value is small.5) with weak cementation of overlying rock strata dynamic moving process based on the established unconsolidated mining overburden rock strata movement mechanics model. And the mechanical model as the theoretical basis, combined with the material mechanics knowledge, deduces the new weak rock cementation mining caving zone development prediction method of highly.6) theoretical analysis in unconsolidated overburden subsidence coefficient is less than four a factor of experience mining soft rock conditions in eastern China under the sink coefficient. Three main factors: weak cemented rock hydration expansion factors, like "overburden grouting" factors, alluvial sand flow One of the main factors; factors: thick characteristic factors of strata. The thick rock characteristics resulted in similar to the eastern coal mine hard rock anti deformation process of the deformation in the transfer to the surface rock movement.

【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD325

【参考文献】