采矿与安全工程学报 ›› 2015, Vol. 32 ›› Issue (4): 665-670.

• 论文 • 上一篇    下一篇

含水煤样破裂过程中的声发射及分形特性研究

  

  1. 1.煤炭安全生产河南省协同创新中心,河南焦作 454003;2.河南理工大学河南省瓦斯地质与瓦斯治理重点实验室-省部共建国家重点实验室培育基地, 安全科学与工程学院,河南焦作 454003
  • 收稿日期:2013-12-30 出版日期:2015-07-15 发布日期:2019-09-02
  • 作者简介:高保彬(1977—),男,河南省民权县人,讲师,博士,从事矿山安全开采方面的研究。
  • 基金资助:

    国家自然科学基金委员会-河南省人民政府人才培养联合基金项目(U1304502);河南省重点实验室基金项目(WS2012B06);河南省教育厅自然科学基金项目(12A440004)

Acoustic emission and fractal characteristics of saturated coal samples in the failure process

  • Received:2013-12-30 Online:2015-07-15 Published:2019-09-02

摘要: 为了研究含水煤样破裂过程中的声发射及分形特征,以余吾煤业 3#煤层煤样为研究对象,利用RMT-150C 型岩石力学伺服试验系统和AE-win E1.86 型声发射监测仪,分别对干燥、自然和饱和煤样进行单轴压缩下的声发射试验,对声发射计数序列进行了分形特征分析。研究结果表明:含水量的增加会造成单轴抗压强度的降低;3 种状态煤样破裂过程中的声发射参数的演化过程大致相同,可以分为3 个阶段,即初始声发射平静期、声发射活跃期和峰后声发射平静期;自然煤样与干燥煤样相比,声发射计数下降了49.95%,声发射累计计数下降了37.04%;饱和煤样与干燥煤样相比,声发射计数下降了77.48%,声发射累计计数下降了52.17%;干燥煤样、自然煤样和饱和煤样破裂过程中都具有分形特征,声发射计数分维值都会出现波动上升→突降→最大值的现象,这可以作为一种煤岩动力灾害预测的前兆信息。

关键词: 饱和煤样, 声发射, 单轴压缩, 分形, 关联维数

Abstract: To study the acoustic emission (AE) and fractal characteristics of saturated coal samples, focusing on coal samples of No.3 coal seam in Yuwu coal mine, an experimental study was carried out to investigate the acoustic emission characteristics of the dry, natural and saturated coal samples under uniaxial compression, by using RMT-150C rock mechanics test system and AE-win E1.86 acoustic emission instrument, and the fractal characteristics of acoustic emission count sequence was further analyzed. The results show that the uniaxial compressive strength decreases when the water content of coal samples increases. The acoustic emission evolution processes of dry, natural and saturated coal samples are similar, which can be divided into three stages, that is, the initial quiet period, the active period, and the post peak quiet period. Compared with the dry coal samples, the acoustic emission count of natural coal samples reduces 49.95%, and the cumulative acoustic emission count reduces 37.04%,while the acoustic emission count of saturated coal samples reduces 77.48%, and the cumulative acoustic emission count reduces 52.17%. All of the dry, natural and saturated coal samples have the fractal characteristics, and the fractal dimension value of acoustic emission presents the phenomenon of rising, drop and maximal value, which can be used as the precursor information of dynamic disaster prediction.

Key words: saturated coal sample, acoustic emission, uniaxial compression, fractal, correlation dimension