【摘要】 为研究煤岩电信号产生机理,以利用电信号预测煤岩动力灾害,选用煤、花岗岩、砂岩等不同性质煤岩体,利用建立的试验系统分析了煤岩温度、煤岩性质、煤岩摩擦、煤岩加载速度及煤岩载荷等因素对煤岩电信号的影响。结果表明:随温度升高过程中,煤岩电信号的变化规律可分为3个阶段;性质不同的煤岩体单轴压缩下产生的电信号幅值有明显差别;煤岩摩擦过程中能产生电信号;随加载速度增大,煤岩即将破裂时产生的电信号有增强趋势;电信号大小与载荷大小不成比例关系,但在即将破裂时产生的电信号最大。更多还原

【Abstract】 This paper is aimed at introducing our study results on the working principle for generating the electric signals of the coal and rocks.The research topic is of great significance because such signals of the coal and rocks can help to predict and forecast the mining dynamic disasters and differentiate the particular characteristic features of coal,granite,sandstone and other coal-rock mass in the process of coal mining.In the research process,we have established testing systems that may influence the temperature of the coal rock,the friction of the coal rock,and the uniaxial compression on the coal rocks,in addition to the coal loading velocity and size of coal load.The chief results can be summarized as follows:the changing laws of the electrical signals can be divided into three stages according to the strength of the signal generation,namely,the weak increase of the electric signals,the slow increase and the quick increase of such signals.At the same temperature,the electrical signals produced by granite tend to be stronger than those produced by sandstone.At the same temperature,the electrical signals produced by granite are stronger than those produced by the sandstone.On the other hand,the signal amplitudes which are produced by different kinds of coal-rock mass under uniaxial compression can also be obviously different.The maximal electrical signals that are produced by granite can be twice as much as those produced by the coal whereas the maximal electrical signals produced by coal can be stronger than those produced by the sandstone.As to the friction of the coal rock,it can produce the electrical signals in two stages.That is to say,the electric signals exist in the real process of friction,on the one hand,the signals of the coal rock increase with the extension of friction time,and,on the other hand,the signals tend to be stable with the increase of friction time.With the increase of the loading velocity,there can also be found an increasing trend in generation of the electrical signals particularly when the coal rock is going to burst or explode.Though,there does not exist proportional relationship between the signal size and the load size,the generation rate of which is likely to go to the maximal when the coal rocks are about to burst.Thus,our analysis on the influential factors of the rock electrical signals is so significant as to be able to provide reference and information guide to the forecast and prediction of coal mining disasters such as coal mining fire or underground water floods.更多还原