回采工作面冲击地压声电监测阈值的确定

Determination of threshold value of acoustic emission and electromagnetic radiation synchronized monitoring technology during mining process

针对巴彦高勒煤矿坚硬厚顶板煤层在回采期间出现过煤壁片帮、顶板下沉等动力显现现象,以其311305工作面为工程背景,在该工作面的回风顺槽和运输顺槽生产帮各布置40个超前测点,利用YDD-16型声发射电磁辐射联合监测仪对该工作面超前400 m区域进行动态监测以及危险预警,根据现场监测数据并结合模糊数学判别模型,研究了该工作面超前区域声电监测信号时空演变规律,分析了声电监测信号强度与冲击地压显现前兆之间的对应关系,确定了该矿类似生产条件下回采工作面冲击地压声电监测阈值。研究结果表明:超前测点的声电信号监测波形曲线能够很好地反映工作面超前支承应力的分布特征及分布范围;声电信号在工作面周期来压以及过强冲击危险性区域时具有显著增大的趋势;通过模糊数学的方法,计算得出311305工作面的声发射预警值为168 mV,电磁辐射预警值为28 mV,研究结果为保证矿井工作面安全高效生产提供了科学依据。

There frequently occur the coal wall spalling and the roof subsidence during coal mining process,in view of the hard and thick coal seam in Bayangol coal mine,taking 311305 work face as the engineering background,and YDD-16 type acoustic and electrical monitoring device are used to monitor the dynamic change of coal seam roof,and 40 advanced measuring points are arranged in the air return way and transportation way advanced work face area 400 m respectively.The relationship between the change of acoustic and rockburst is studied.The conclusions are as follows:the acoustic and electrical monitoring waveform curve can well reflect the distribution characteristic of the advance support stress of mining face,the acoustic and electrical signal has a significant increase trend when periodic weighting in coal mine face;fuzzy mathematic is applied to set up the acoustic and electrical signal threshold value of 311305 mining face,the acoustic and electrical threshold value is 168 mV and 28 mV,respectively;and the research results provide a scientific basis for the study of rockburst monitoring and early warning.