This paper has put forward a concept of optimal supporting time through analysing the influence of the supporting time in the heading face on the supporting result of surrounding rock.The method Of the optimal Support...This paper has put forward a concept of optimal supporting time through analysing the influence of the supporting time in the heading face on the supporting result of surrounding rock.The method Of the optimal Supporting time determined by graphical method is discussed, and the calculating formula for determining the optimal supporting time through the analysis method is derived.展开更多
Based on the complexity and dynamic random analysis of machine noise source in mine heading face, this article established the noise pressure mathematical model of noise propagation in mine laneway of different noise ...Based on the complexity and dynamic random analysis of machine noise source in mine heading face, this article established the noise pressure mathematical model of noise propagation in mine laneway of different noise sources, carried out noise propagation numerical simulation in long space, and revealed noise propagation law of more radiated noise sources in the mine roadway. The results show that, under conditions that the total noise power is always the same, regardless of point source, surface noise source, or body noise source, the corresponding noise attenuation trend along the mine laneway and attenuation curve shape are basically the same. However, the attenuation velocity corresponding to complex stereo noise source is slower than single point source and the noise pressure value is higher than the single point source. The actual noise of measured values is close to the theoretical value or, say, there is little error for complex stereo noise source, whereas the error to single point source and surface noise is higher, respectively.展开更多
The three-dimensional damage constitutive relationship of coal is established and distribution law of the abutment pressure of the integrated coal beside the road-in packing for gob-side entry retaining in fully-mecha...The three-dimensional damage constitutive relationship of coal is established and distribution law of the abutment pressure of the integrated coal beside the road-in packing for gob-side entry retaining in fully-mechanized caving face under the effect of given deformation of the main roof is analyzed by the damage mechanics theory. And the relationship between distribution of the abutment pressure and thickness of coal seam is explored. The presented result is of great theoretical significance and practical value to the study on stability control of the surrounding rock of road-in packing for gob-side entry retaining in fully-mechanized caving face.展开更多
文摘This paper has put forward a concept of optimal supporting time through analysing the influence of the supporting time in the heading face on the supporting result of surrounding rock.The method Of the optimal Supporting time determined by graphical method is discussed, and the calculating formula for determining the optimal supporting time through the analysis method is derived.
基金Supported by the National Natural Science Foundation of China (50975087) the Scientific Research Starting Foundation for Returned Overseas Chinese Scholars, Ministry of Education, China ([2009] 1590) the Key Research Project of Hunan Province Office of Education (09A026)
文摘Based on the complexity and dynamic random analysis of machine noise source in mine heading face, this article established the noise pressure mathematical model of noise propagation in mine laneway of different noise sources, carried out noise propagation numerical simulation in long space, and revealed noise propagation law of more radiated noise sources in the mine roadway. The results show that, under conditions that the total noise power is always the same, regardless of point source, surface noise source, or body noise source, the corresponding noise attenuation trend along the mine laneway and attenuation curve shape are basically the same. However, the attenuation velocity corresponding to complex stereo noise source is slower than single point source and the noise pressure value is higher than the single point source. The actual noise of measured values is close to the theoretical value or, say, there is little error for complex stereo noise source, whereas the error to single point source and surface noise is higher, respectively.
基金Supported by the National Science Foundation of China (50874042, 50674046)National Science Important Foundation (50634050)Hunan Science Foundation (06JJ50092)
文摘The three-dimensional damage constitutive relationship of coal is established and distribution law of the abutment pressure of the integrated coal beside the road-in packing for gob-side entry retaining in fully-mechanized caving face under the effect of given deformation of the main roof is analyzed by the damage mechanics theory. And the relationship between distribution of the abutment pressure and thickness of coal seam is explored. The presented result is of great theoretical significance and practical value to the study on stability control of the surrounding rock of road-in packing for gob-side entry retaining in fully-mechanized caving face.