温度-围压-瓦斯作用下煤岩强度和脆性变化分析

Analysis of Strength and Brittleness of Coal and Rock under Influence of Temperature-Confining Pressure-Gas

利用正交试验法设计安排了9组煤样的单三轴压缩实验,提出了一种基于峰前弹性模量和峰后模量的脆性指标,利用统计学方法分析了温度、围压、瓦斯对煤样强度和脆性指标的影响。得出:围压和瓦斯对煤样强度影响的显著性水平均在99%以上,对脆性指标影响的显著性分别在99%和97%,温度对煤岩强度和脆性指标的影响显著性水平较低;分析了各因素对煤样强度和脆性的作用机理,利用线性模型对各因素作用下的煤样强度以及脆性指标进行了拟合,揭示了各因素作用下煤样强度和脆性的变化规律。

The compressive experiment of 9 groups of coal samples was arranged by orthogonal test, abrittleness index based on pre-peak elastic modulus and post - peak modulus was proposed. Theinfluence of temperature, confining pressure and gas on the strength and brittleness of coal samples wasanalyzed by statistical method. The results showed that the significant effects of confining pressure andgas on the strength of coal were above 99%, and the significant effects on the brittle index were 99%and 97%, respectively, the effect of temperature on the strength and brittleness of coal and rock has asignificant significance level. The effects of various factors on the strength and brittleness of coalsamples were analyzed. The linear model was used to fit the coal strength and brittleness underdifferent factors, the changes of coal strength and brittleness under different factors were revealed.