Time filter

Source Type

Wang H.,Guizhou Key Laboratory of Comprehensive Utilization of Non metallic Mineral Resources | Wang H.,Northeastern University China | Wang H.,Guizhou University | Yang T.-H.,Northeastern University China | And 3 more authors.
Meitan Xuebao/Journal of the China Coal Society | Year: 2015

Microstructure research indicated that the sandstones taken from the seam roof of Xiaojihan coal mine in Yuheng mining area are weak cemented sandstones. The triaxial compression tests under different confining pressures for the specimen were conducted using TAW-2000 servo testing machine. The test results show that the sandstone exhibits significant compaction pressure phenomenon at the initial stage and the stage length decreases with confining pressure. When entering the plastic stage, the transition from rigidity to plastic obviously increases with confining pressure. Furthermore, the pressure transition before or after the yield point is described and analyzed using two-parts hook's model (TPHM) and statistical damage model respectively. The model curves and experimental curves have a good match. This demonstrates that the TPHM model expresses the nonlinear elastic deformation and elastic deformation very well before the rock damage, and the statistical damage model fits the deformation of rock after damage well. © 2015, China Coal Society. All right reserved.

Chi E.-A.,Wuhan University of Technology | Chi E.-A.,Guizhou University | Zhang Y.-P.,Guizhou University | Zhang Y.-P.,Guizhou Key Laboratory of Comprehensive Utilization of Non metallic Mineral Resources
Journal of Coal Science and Engineering | Year: 2010

The mechanism of ground vibration in building demolition blasting was investigated, taking into account the prevailing influential factors, including the building's height of mass center, the quantity size, the structural feature, the component material quantity, the demolition method, the geological structure of the region, earthquake resistance rank, as well as the earthquake wave dissemination. The proposed method was applied efficiently to reduce the blasting effects on the environment, which enriches the control theories of vibration caused by collapse in the blasting process and may provide a good reference for the related engineering practices. © The Editorial Office of Journal of Coal Science and Engineering (China) and Springer-Verlag Berlin Heidelberg 2010.

Dai Z.Y.,Guizhou University | Dai Z.Y.,Guizhou Key Laboratory of Comprehensive Utilization of Non metallic Mineral Resources
Advanced Materials Research | Year: 2014

With analyzing the shortcomings of "Success Tree" method, the article proposed two new algorithms which base on the basic principles of Boolean algebra and Fussell determinant method respectively to replace the "success tree" method to solve the minimum path sets of fault tree. Combined with the simple and the complex examples' results, the correctness and effectiveness of new algorithms were verified. Especially for the large and complex fault trees, the solving process of these new algorithms can be simplified sharply. Furthermore, the new algorithms could provide the algorithm support for the realization of quantifying the qualitative analysis, modeling the quantitative analysis, and computerizing the model analysis. © (2014) Trans Tech Publications, Switzerland.

Xu J.,Chongqing University | Yuan M.,Chongqing University | Yuan M.,Guizhou University | Yuan M.,Guizhou Key Laboratory of Comprehensive Utilization of Non metallic Mineral Resources | And 2 more authors.
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2012

Internal and external pore characteristics of raw coal sample of medium and high degrees of metamorphism which were obtained from Liupanshui mining area were studied by using TESCAN VEGA II scanning electron microscope (SEM)-energy-dispersive X-ray (EDX) and ASAP2020 specific surface microanalyzer. Triaxial seepage experiments of constant different gas pressures were carried out by independently developed traixial seepage device. The results show that: (1) There is positive correlation between metamorphic grade of coal and interior and external pore characteristics. The higher the metamorphic grade is, the higher the fractal dimension is and the greater the raw coal adsorption capacity and pore volume are. (2) There is also positive correlation between internal and external pore characteristics of raw coal and permeability. The more developed the internal and external pore, the greater the permeability is. (3) Under the conditions of constant mean effective stress and temperature, with the increasing gas pressure, at first the permeability sharply decreases and then tends to decrease gradually; and the relationship between permeability and gas pressure obeys exponential distribution. The research results have some theoretical significance to gas disaster prevention and development and utilization of coalbed methane of Liupanshui mining area.

Cheng W.,Guizhou University | Yang R.-D.,Guizhou University | Zhang Q.,Guizhou University | Zhang Q.,Guizhou Key Laboratory of Comprehensive Utilization of Non metallic Mineral Resources | And 2 more authors.
Meitan Xuebao/Journal of the China Coal Society | Year: 2013

Based on thirteen exploratory reports for coal mines form Bijie City, Guizhou Province, data about basic coal features such as sulphur content, ash yield, ash composition and concentration of eleven trace elements as Ge, Ga, U, Th, V, Cl, As, F, Pb, Cu and Zn was systematically analyzed and modeled, and the distribution characteristics, occurrence modes and controlling factors of those trace elements in Bijie coal were investigated. In order to obtain a relative accurate content level of those eleven trace elements in Bijie coal, a parameter called "Reserves Weight Coefficient" was applied. Results show that in Bijie coal Pb, Cu, Zn, U and V are abnormally enriched, Ga is relatively enriched, F and Th are slightly enriched while Ge and Cl are both lower than the Clarke Value, concentration of As in Bijie coal is higher than the common Chinese coal but markedly lower than the USA coal. Correlativity analysis reveals that F may occurs in carbonate minerals, Pb and Cu are probably hosted in sulphide minerals and Cu shows a certain degree of organic affinity. Evidence suggests that on the one hand enrichment of Cu, Zn and V in Bijie coal can be attributed to Emeishan basalt in terrigenous province whose content of those three elements are relatively high; on the other hand trace elements enrichment in coal are controlled by sedimentary environment, specifically some elements that migrate easily in continental sedimentation process such as Ge, Ga and Th tend to be of higher content in coal when the seawater influence is weakening. V is enriched in coal when the influence is strong. In addition, some elements' abnormal enrichment in Bijie coal is believed to be linked with the tectonic movement especially hydrothermal fluid.

Discover hidden collaborations