摘要
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 paste backfill working face 2351 for an example in Daizhuang coal mine, bearing characteristics of filling body and supporting intensity of working face during coal pillar mined with paste backfill have been studied. Based on the analysis of the motion characteristics of roof in coal pillar mined with paste backfill, the mechanical model of roof stability during coal pillar mined with paste backfill has been established, and the mechanics related formula of supporting intensity has also been concluded. Research has shown that： the strength of paste is high, elastic modulus and Poisson＇s ratio are lower, the discreteness of mechanical properties is obvious, and that the paste has typical plasticity hardening features; The overlying strata of paste backfill working face has breaks, bed separation and bending zone rather than caving zone; The distribution of vertical stress above the filling body is not a horizontal line nor saddle-shaped as the strip coal pillar but presents wave distribution. The stress above the filling body is not mutational but tends to be increasing and stable at last. The hydraulic supports used in paste backfill face 2351 can control the roof subsidence effectively, but the efficiency of hydraulic supports is lower, which should be optimized properly.
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2016年第4期585-591,共7页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(51274132,U1361105)
教育部博士点基金项目(20133718110001)
山东省自然科学基金重点项目(ZR2013EEZ001)
关键词
条带煤柱
膏体置换开采
充填体承载特性
工作面支护强度
strip coal pillar
paste backfill mining
bearing characteristics of filling body
supporting intensity of working face
