中国安全科学学报 ›› 2021, Vol. 31 ›› Issue (8): 104-111.doi: 10.16265/j.cnki.issn1003-3033.2021.08.015

• 安全工程技术 • 上一篇    下一篇

煤岩自振频率的影响因素试验研究*

任永婕1, 魏建平1,2,3 教授, 温志辉**1,2 副教授, 张俊昭1, 姚帅1   

  1. 1 河南理工大学 安全科学与工程学院,河南 焦作 454003;
    2 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,河南 焦作 454003;
    3 煤炭安全生产与清洁高效利用省部共建协同创新中心,河南 焦作 454003
  • 收稿日期:2021-05-28 修回日期:2021-07-12 出版日期:2021-08-28 发布日期:2022-02-28
  • 通讯作者: ** 温志辉(1982—),男,河北邢台人,博士,副教授,主要从事煤矿瓦斯灾害预测与防治等方面的教学和研究工作。E-mail:wenzhihui@hpu.edu.cn。
  • 作者简介:任永婕 (1995—),女,河南新乡人,博士研究生,研究方向为矿井瓦斯防治。E-mail:15565436676@163.com。
  • 基金资助:
    国家自然科学基金资助(51974109);中原科技创新领军人才项目(204200510032);河南省科技攻关项目(202102310220)。

Experimental research on influencing factors of natural frequency of coal

REN Yongjie1, WEI Jianping1,2,3, WEN Zhihui1,2, ZHANG Junzhao1, YAO Shuai1   

  1. 1 School of Safety Science and Engineering, Henan Polytechnic University, Jiaozuo Henan 454003, China;
    2 State Key Laboratory Breeding Base of Henan Province Key Laboratory of Gas Geology and Gas Control, Henan Polytechnic University, Jiaozuo Henan 454003, China;
    3 State Collaborative Innovation Center of Coal Work Safety and Clean-efficiency Utilization, Jiaozuo Henan 454003, China
  • Received:2021-05-28 Revised:2021-07-12 Online:2021-08-28 Published:2022-02-28

摘要: 为探究振动波增渗煤岩的优势频率,依据敲击法测试原理自主搭建煤岩自振频率测试系统,从煤岩尺寸、含水率及孔洞缺陷等3方面,研究煤岩的自振频率。研究结果表明:进行振动信号的快速傅里叶变换(FFT)时,汉宁窗较矩形窗、指数窗的加窗效果更好;在此基础上,测得4组不同尺寸煤岩的一阶、二阶自振频率范围分别为11.1~17.2 Hz、35.0~40.6 Hz;含水率的增加使得煤岩自振频率降低,且煤岩的一阶自振频率变化在含水率较低时较敏感;煤岩孔洞体积对其自振频率的影响存在局限性,不同孔洞体积煤岩的一阶、二阶自振频率变化幅值分别在5.2%、6.5%之内;振动波对煤岩自振频率影响以塑性变形及煤岩整体缺陷的演化为主。

关键词: 煤岩, 自振频率, 窗函数, 含水率, 孔洞体积

Abstract: In order to explore dominant frequency of vibration wave increasing permeability of coal, a coal natural frequency test system was built based on knocking method test principle, and coal natural frequency was studied from three aspects: coal size, moisture content, and hole defects. The research results show that Hanning window is better than rectangular window and exponential window in FFT analysis of vibration signal. On this basis, ranges of the first-order and second-order natural frequencies for four different coal groups are 11.1-17.2 Hz and 35.0-40.6 Hz, respectively. Increase of moisture content reduces coal natural frequency, and variation of first-order natural frequency is more sensitive when moisture content is lower. Influence of hole volume on natural frequency of coal has limitations. Variation amplitude of the first and second natural frequencies of coal with different pore volume is within 5.2% and 6.5% respectively. Main influences of vibration wave on coal natural frequency are plastic deformation and evolution of whole defect of coal.

Key words: coal, natural frequency, window function, moisture content, hole volume

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