论文部分内容阅读
以山东能源集团岱庄煤矿2351膏体充填置换条带煤柱工作面为例,对井下充填体承载特性及工作面支护强度进行了研究。在分析膏体充填开采顶板运动特征的基础上,建立了膏体充填开采顶板稳定性力学模型,推导出了膏体充填开采工作面支护强度力学关系式。结果表明:膏体的力学性质离散性较大,强度较高,弹性模量和泊松比偏低,在低围压下膏体即表现出典型的塑性强化特性。充填采场上覆岩层主要存在裂缝、离层和弯曲下沉,不存在垮落带。充填体上分布的垂直应力既不是大小相同的水平线,也不是类似于条带煤柱上的马鞍形分布,而呈现出波浪形分布,自充填完成至覆岩运动稳定,充填体受力未出现突变现象,是一个逐步增大并趋于稳定的过程。2351膏体充填工作面现选用的充填式液压支架虽可有效地控制顶板下沉,但未能发挥所选支架的效能,还可进行适当优化。
Taking Shandong Province Energy Group Daihuang Coal Mine 2351 Paste Filling and Replacement Coal Pillar Face as an example, bearing capacity and working face supporting strength are studied. Based on the analysis of the roof movement characteristics of the paste filling mining, the mechanical model of the roof stability of the paste filling mining was established and the mechanical relationship between the support strength of the paste filling and mining working face was deduced. The results show that the mechanical properties of the paste are more discrete, higher strength, lower elastic modulus and Poisson’s ratio, and the paste exhibits typical plastic strengthening properties under low confining pressure. There are mainly cracks in overlying strata of filling stope, falling from strata and bending, and there is no caving zone. The vertical stress distributed on the filling body is neither the horizontal line of the same size nor the saddle-shaped distribution similar to that of the strip coal pillar, but presents the wavy distribution, and the stress of the filling body does not appear from the completion of the filling to the stability of the overburden rock Mutation phenomenon is a process of gradual increase and stabilization. 2351 Paste Filling Face The currently available filling hydraulic supports effectively control roof subsidence but fail to perform as well as optimize the performance of the selected bracket.