Liu J.,Northeastern University China |
Liu Z.,Northern Engineering and Technology Corporation |
Wang S.,Northern Engineering and Technology Corporation |
Shi C.,Northeastern University China |
And 2 more authors.
International Journal of Mining Science and Technology
Aiming at evaluating the stability of a rock mass near a fault, a microseismic (MS) monitoring system was established in Hongtoushan copper mine. The distribution of displacement and log(EI), the relationship between MS activity and the exploitation process, and the stability of the rock mass controlled by a fault were studied. The results obtained from microseismic data showed that MS events were mainly concentrated at the footwall of the fault. When the distance to the fault exceeded 20 m, the rock mass reached a relatively stable state. MS activity is closely related to the mining process. Under the strong disturbance from blasting, the initiation and propagation of cracks is much faster. MS activity belongs in the category of aftershocks after large scale excavation. The displacement and log(EI) obtained from MS events can reflect the difference in physical and mechanical behavior of different areas within the rock mass, which is useful in judging the integrity and degradation of the rock mass. © 2016 Published by Elsevier B.V. on behalf of China University of Mining & Technology. Source
Liu J.-P.,Northeastern University China |
Shi C.-Y.,Fushun Hongtoushan Mining Co. |
Li Y.-H.,Northeastern University China |
Zhang F.-P.,Northeastern University China |
And 2 more authors.
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering
In this paper, in view of the serious conditions of ground pressure (rock burst, etc) appeared in Hongtoushan copper mine, we established a microseismic monitoring system in the mine, and analyzed the relationship between the microseismic activities and mining operation, and the spatial distribution of microseismic events, applied the energy index and apparent volume to forecast the occurrence of large scale rock fracturing. The location results using manual fixed-point blasting show that the location error of microseismic monitoring system is less than 10m, which suggests that the system can reach the requirement for ground pressure disaster monitoring in mine. Microseismic activities can be divided into two quiet periods and three active periods. There exits the incubation and early-warming periods before the large scale rock fracturing. The quick drop of energy index and the continuous increase of apparent volume can be used as the precursory characteristics of rock burst and large scale rock fracturing. Through the cloud charts of energy index and displacement, the potential danger areas of ground pressure disasters can be judged, which can be used to guide the safety management and ensure safety production in deep mine. Source