基于钻进声压响应特征巷道顶板岩层界面识别的研究

Research on recognition of roadway roof rock layer interface based on sound pressure response characteristics of drilling

目前,岩石取芯和钻孔成像仍是煤矿岩层探测的主要方法,但岩石取芯费时、费力,且难以得到软弱夹层的岩样,钻孔成像法存在成像不清晰,受主观因素影响大等问题。本文提出了一种基于钻进声压响应特征岩层界面快速识别的新方法。以水泥、沙子、黄土、水按不同比例配比成3种强度的混凝土试件,采用声压记录仪采集了各试件钻进过程中的声压;在某矿504回风平巷进行现场试验。通过试验得出如下结论:①随着钻进试件强度增高声压也随之增大;②不同强度试件钻进过程中声压变化较小,而同种试件中钻进时声压也存在一定波动;③以钻进声压为单一指标煤岩界面识别误差达15 cm,但提供了一种岩层识别的新方法,是岩层智能探测的主要方向,为后续研究提供了参考。

Currently,rock coring and borehole imaging are widely used in the field of rock formation detection in coal mines.However,the rock coring is time-consuming,laborious,and it is very difficult to obtain rock samples with weak interlayers.The borehole imaging method is greatly affected by subjective factors,and the imaging is not clear due to the harsh environment.A new method for rapid identification of rock formation interface based on the drilling response characteristics of sound pressure is proposed in this paper.Cement,sand,loess,and water are mixed into concrete specimens with three different strengths in different proportions,and the sound pressure of each specimen is collected during the drilling process with a sound pressure recorder.And the field test is carried out in 504 return airway in a mine.The following conclusions are drawn.The sound pressure increases as the strength of the drilling specimen increases.The sound pressure changes little during drilling in different specimens,and there are certain fluctuations in the sound pressure when drilling in the same specimens.The recognition error of coal-rock interface with drilling sound pressure as a single indicator is up to 15 cm,but it provides a new method for rock formation recognition.Measurement while drilling is the main direction of intelligent rock formation detection.These research conclusions provide references for follow-up scholars.