Huainan Mining Industry Group

Huainan, China

Huainan Mining Industry Group

Huainan, China
SEARCH FILTERS
Time filter
Source Type

Yao Q.,China University of Mining and Technology | Yao Q.,Key Laboratory of Deep Coal Resource Mining CUMT | Li X.,China University of Mining and Technology | Li X.,Key Laboratory of Deep Coal Resource Mining CUMT | And 7 more authors.
Arabian Journal of Geosciences | Year: 2015

We carried out uniaxial compressive experiments on coal specimens with different moisture contents to gain a better understanding of the water-induced weakening characteristics of coal. The effects of moisture content on the strength and deformation characteristics of the specimens were analyzed. The results of the uniaxial compressive experiment demonstrate that the full stress–strain curve presents plastic deformation characteristics with the increase of the moisture content in the coal specimens. A positive linear relation between the peak strain and moisture content and a negative one between the compressive strength and moisture content were observed. The results also show that the elastic modulus and the moisture content satisfy a negative exponential function. Taking the obtained relation as boundary conditions and applying the statistical damage theory and strain equivalence hypothesis, we derived a statistical constitutive damage model for coal which can reflect the effects of the moisture content. © 2015, Saudi Society for Geosciences.


Lu C.-P.,China University of Mining and Technology | Lu C.-P.,Pennsylvania State University | Dou L.-M.,China University of Mining and Technology | Zhang N.,China University of Mining and Technology | And 4 more authors.
International Journal of Rock Mechanics and Mining Sciences | Year: 2013

Strong rockburst disaster in deep coal mines is easily triggered by the higher static stress of mining coal seam and the dynamic stress wave disturbance generated by hard and thick roof fall. Revealing the frequency-spectrum evolutionary rule of microseismic (MS) signals before and after roof fall is a very important issue for evaluating and forecasting rockburst danger. By experimental tests for combined coal and rock samples rockburst failure and in-situ measurements in a strong rockburst coal mine, the frequency-spectrum evolutionary rule and precursory characters were analyzed in detail. The following conclusions were drawn: (1) Precursory MS signals show the elevated energy and events, lower frequency and trend of spectrum moving to low-frequency band; (2) mainshock signals of rockburst are characterized by maximum amplitude (vibration velocity), wider spectrum, and higher predominant frequency; and (3) aftershock signals are characterized by the sudden decreasing amplitude, highest predominant frequency, and trend of spectrum moving to high-frequency band. © 2013 Elsevier Ltd.


Lu C.-P.,Anhui University of Science and Technology | Lu C.-P.,China University of Mining and Technology | Liu G.-J.,China University of Mining and Technology | Wang H.-Y.,China University of Mining and Technology | Xue J.-H.,Huainan Mining Industry Group
Shock and Vibration | Year: 2015

Using UDEC discrete element numerical simulation software and a cosine wave as vibration source, the whole process of rockburst failure and the propagation and attenuation characteristics of shock wave in coal-rock medium were investigated in detail based on the geological and mining conditions of 1111(1) working face at Zhuji coal mine. Simultaneously, by changing the thickness and strength of immediate roof overlying the mining coal seam, the whole process of rockburst failure of roadway and the attenuation properties of shock wave were understood clearly. The presented conclusions can provide some important references to prevent and control rockburst hazards triggered by shock wave interferences in deep coal mines. © 2015 Cai-Ping Lu et al.


Lu C.-P.,China University of Mining and Technology | Lu C.-P.,Pennsylvania State University | Dou L.-M.,China University of Mining and Technology | Zhang N.,China University of Mining and Technology | And 2 more authors.
Natural Hazards | Year: 2014

It has a significant and practical meaning for warning precisely gas outburst to reveal microseismic (MS) and acoustic emission (AE) effect of gas outburst precursor. It was thoroughly investigated and discussed on MS and AE effect on an abnormal gas outburst triggered by a strong rockburst using MS- and AE-monitoring systems through spectral analysis technique. We obtained main conclusions are as: (1) MS amplitude prominently decreased prior to outburst, the spectrum significantly moved from extremely low-frequency to high-frequency band, and evolved from "single-peak type" (the center frequency was about 1.5-3.5 Hz) to "multi-peak type" (the peak frequencies were about 25, 50, 75 and 125 Hz, respectively). (2) During the initiative stage of outburst, MS spectrum manifested the broadband distribution, and the predominant frequency was about 20-35 Hz. The high-frequency portion was generated by micro-cracks, and the low-frequency part attributed to macro-fracture for gas outburst channel. (3) The rockburst stimulated micro-fissures formation for gas emission channels, and maintained the event count of MS and AE signals in a relatively higher level, which is a major discrepancy to the common belief that both the total energy and event count should simultaneously and suddenly reduce to the lowest value in a non-outburst coal seam. © 2014 Springer Science+Business Media Dordrecht.


Wang X.-N.,China University of Mining and Technology | Lu C.-P.,China University of Mining and Technology | Lu C.-P.,Pennsylvania State University | Xue J.-H.,Huainan Mining Industry Group | And 4 more authors.
Yantu Lixue/Rock and Soil Mechanics | Year: 2013

The acoustic emission (AE) and microseismic (MS) rules in the process of deformation and failure of samples combined with roof, coal and floor are very important to reveal the dynamic mechanism of rockburst. The compound samples were tested by SANS material testing system under uniaxial compression condition. During the whole test process, the AE and MS events were monitored by DISP-24 AE system and TDS-6 MS collection system. The results showed that the larger the uniaxial compressive strength, rockburst tendency and the ratio of roof height to coal height of compound samples are, the stronger the intensity of AE and MS signal is. The amplitude of MS signal can reflect the rockburst tendency of compound samples. The spectrum distribution of MS signal in the high frequency band will increase along with the increasing compressive strength and impact energy index of samples. The above conclusions are of great significance to evaluate, monitor and warn rockburst in coal mines.

Loading Huainan Mining Industry Group collaborators
Loading Huainan Mining Industry Group collaborators