神东浅埋工作面矿压显现规律的多因素耦合分析

针对神东矿区浅埋工作面矿压显现特征,结合126例浅埋工作面矿压实测数据采用回归分析、概率统计手段,分别就工作面覆岩岩性、采高、埋深及工作面长度对工作面矿压最大值、载荷分布及来压步距影响进行单一及耦合分析,提出覆岩硬度系数法来数值化覆岩岩性并结合KSPB软件归类覆岩,结果表明:1覆岩岩性、采高、埋深及工作面长度与工作面矿压最大值分别呈线性、线性、负对数及正双对数函数相关,无关键层、单一关键层及多关键层下相关参数不同;2工作面斜长上矿压呈二次函数分布,载荷分布系数a与工作面长度呈负对数相关,无、单一及多关键层下相关参数不同,且覆岩岩性、采高、埋深对工作面矿压分布影响较小;3工作面初次、周期来压步距与覆岩硬度系数呈正指数相关,与采高、埋深及工作面长度呈概率分布相关,无关键层、单一关键层及多关键层下相关参数不同,覆岩硬度系数预测值与概率统计值的并集为工作面初次、周期来压步距预测值。对比分析及工程实践表明,经验回归公式结合概率统计分析在一定残差范围内可准确预测浅埋工作面矿压最大值、载荷分布规律及初次、周期来压步距。

A multi-coupling analysis of mining-induced pressure characteristics of shallow-depth coal face in Shendong mining area

For shallow-depth mining-induced pressure characteristics of Shendong mines,combining with 126 cases of shallow buried coal face pressure measurement data,the regression analysis and probability statistics analysis were conducted regarding the single and coupling influences on the maximum mining-induced pressure,pressure distribution and pressure step caused by overlying strata lithology,mining height,buried depth and face length.At the same time,KSPB software and overburden rock hardness coefficient method were used to quantify the strata lithology.The results show that (1) Under the condition of no,single and multiple key stratums,the strata lithology,mining height,buried depth and face length have the relationship of linear,linear,negative logarithm and double logarithmic function with maximum mining-induced pressure,and different strata lithology conditions have different parameters；(2) Pressure distribution has the characteristics of the quadratic function on face length direction.When face length increases,the pressure distribution parameter -a decreases with the form of negative logarithmic function,different strata lithology conditions have different parameters,and strata lithology,mining height and buried depth have little influence on pressure distribution；(3) Under different strata lithology situations,in working face,first and periodic pressure step have the relationship of exponential function with strata hardness coefficient,and mining height,buried depth and length of working face are related to probability distribution,and the union values of strata hardness coefficient of expected value and probability statistics value are the face first and periodic pressure step.Comparative analysis and engineering practice show that experience regression formula combining with probability statistics,within a certain residual,can accurately estimate the shallow buried coal face maximum pressure,pressure distribution and the pressure step of coal face,providing a reference for the selection of hydraulic support and the control of face roof in similar geological conditions.