IDEAS home Printed from https://ideas.repec.org/a/gam/jsusta/v14y2022i15p9175-d872583.html
   My bibliography  Save this article

Dynamic Response Characteristics and Damage Evolution of Multi-Layer Combined Coal and Rock Mass under Impact Loading

Author

Listed:
  • Feng Li

    (School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China)

  • Runchuan Sun

    (School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China)

  • Yue Zhang

    (CNOOC Research Institute Co., Ltd., Beijing 100028, China)

  • Guanghao Wang

    (School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China)

  • Guangyou Xiang

    (School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China)

Abstract

The areas involved in coal and gas outbursts are composed of multi-layer coal and rock mass, in which external dynamic disturbance propagates in the form of stress waves; therefore, reflection, transmission and diffraction occur at the interfaces, resulting in dynamic effects such as reflected tension, convergence and superposition of stress and strain, and sudden changes of reflected and transmitted stress, which are the key factors leading to the outburst. Based on the Split Hopkinson Pressure Bar system, the dynamic time–history changes of stress, strain and strain rate of five-layer combined coal and rock mass were studied under impact loading. The results show that the time–history curves of stress and strain could be divided into five stages and that of strain rate three stages; the dynamic curves of the five stress–strain stages were significantly different between high-velocity and low-velocity impact. It was hypothesized that under high-speed impact loading, the mechanical anisotropy of combined coal and rock mass at the linear elastic stage tends to be isotropic. Based on ANSYS LS-DYNA, the damage evolution and failure process of five-layer combined coal and rock mass were simulated and analyzed under impact loading. It is concluded that the initial positions of damage of each layer were located at the circle center and its vicinity; radial cracks were mainly formed under low-speed impact loading, and circumferential cracks were mainly formed under high-speed impact loading. In the propagation and action of loading and unloading waves, the “weak layer” was damaged first by tensile stress and formed a free surface, and the subsequent loading waves were reflected on the free surface to form unloading waves and tensile stress, resulting in damage and spalling in multi-layer coal and rock mass.

Suggested Citation

  • Feng Li & Runchuan Sun & Yue Zhang & Guanghao Wang & Guangyou Xiang, 2022. "Dynamic Response Characteristics and Damage Evolution of Multi-Layer Combined Coal and Rock Mass under Impact Loading," Sustainability, MDPI, vol. 14(15), pages 1-13, July.
  • Handle: RePEc:gam:jsusta:v:14:y:2022:i:15:p:9175-:d:872583
    as

    Download full text from publisher

    File URL: https://www.mdpi.com/2071-1050/14/15/9175/pdf
    Download Restriction: no

    File URL: https://www.mdpi.com/2071-1050/14/15/9175/
    Download Restriction: no
    ---><---

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:gam:jsusta:v:14:y:2022:i:15:p:9175-:d:872583. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: MDPI Indexing Manager (email available below). General contact details of provider: https://www.mdpi.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.