The paper presented assessment of sealed fire states in underground coal mines by so-called 'fire characteristic', which graphically described tendencies of fire gas components-oxygen, nitrogen, carbon dioxide...The paper presented assessment of sealed fire states in underground coal mines by so-called 'fire characteristic', which graphically described tendencies of fire gas components-oxygen, nitrogen, carbon dioxide, carbon monoxide and hydrocarbons-in time. In order to mark gas components tendencies in time the authors applied the time series analysis. The case studied confirmed, that analysis of fire gas components tendencies in time and their correlation allow to elicit proper conclusions about fire state assessment. Assessment of fire states based on single value of fire indexes without considering their trends in time and correlation between trends of gas components would give wrong results The suggested method can appropriately indicate fire states in a sealed area.展开更多
Based on the present problems of the support method of gateways in complex surrounding rock in steeply inclined seams, this paper discusses the support selection of lasting gateways in steeply inclined seams, and eval...Based on the present problems of the support method of gateways in complex surrounding rock in steeply inclined seams, this paper discusses the support selection of lasting gateways in steeply inclined seams, and evaluates the support effects. It draws the conclusion that the support of bolt-mesh-anchor is the most effective support of this sort of gateways by using scale model simulation in lab and practice application.The support effects of practice application are satisfactory. It will give a beneficial reference to other analogical mine and has an extensive application prospect.展开更多
Based on the equation of the gas flow continuity and state, Darcy law and Langmuir equation, the law of methane seepage in the wall of drainage roadway was studied. The governing equation of methane one-way seepage in...Based on the equation of the gas flow continuity and state, Darcy law and Langmuir equation, the law of methane seepage in the wall of drainage roadway was studied. The governing equation of methane one-way seepage in the seam was founded. By solving the equation, the calculation of methane seepage velocity in the coal wall was worked out. The result has really applied worth and will give beneficial references to re-lated research, it provides preventing coal and gas outbursts with theoretical gist.展开更多
On the basis of that rock material usually has a larger fracture process zone,a new fracture criterion which is different from that of linear elastic fracture theory was presented.On this basis,the fracture behavior a...On the basis of that rock material usually has a larger fracture process zone,a new fracture criterion which is different from that of linear elastic fracture theory was presented.On this basis,the fracture behavior and influencing factors under modeⅡor compressive shear loading were investigated.展开更多
The Chinese coastal regions are the high risk areas of natural disasters for their lowland and weak and sensitive eco-evironment. The relative sea-level rising (RSLR), resulting from the piling of global sea-level ris...The Chinese coastal regions are the high risk areas of natural disasters for their lowland and weak and sensitive eco-evironment. The relative sea-level rising (RSLR), resulting from the piling of global sea-level rising and regional land subsidence, is to speed up in the 21st century. Certainly the RSLR will exacerbate the land submerging, the disaster from storm-tide and flood-waterlogging and the water shortage, and then affect urban withstanding function, construction safety and eco-resources. According to sustainable development theory, the sustainable utilization of resources and environment and sustainable development of economy and society can both be effectively achieved in coastal regions of China in the 21st century only by the implementation of controlling discharge of greenhouse gas, optimal exploitation of and artificial recharge of ground-water, systematic control of land subsidence, higher design standards for tide and flood controlengineering, improving urban anti-disaster ability, a study on strategy and policy for RSLR and establishment of forecast and pre-warning institution.展开更多
文摘The paper presented assessment of sealed fire states in underground coal mines by so-called 'fire characteristic', which graphically described tendencies of fire gas components-oxygen, nitrogen, carbon dioxide, carbon monoxide and hydrocarbons-in time. In order to mark gas components tendencies in time the authors applied the time series analysis. The case studied confirmed, that analysis of fire gas components tendencies in time and their correlation allow to elicit proper conclusions about fire state assessment. Assessment of fire states based on single value of fire indexes without considering their trends in time and correlation between trends of gas components would give wrong results The suggested method can appropriately indicate fire states in a sealed area.
文摘Based on the present problems of the support method of gateways in complex surrounding rock in steeply inclined seams, this paper discusses the support selection of lasting gateways in steeply inclined seams, and evaluates the support effects. It draws the conclusion that the support of bolt-mesh-anchor is the most effective support of this sort of gateways by using scale model simulation in lab and practice application.The support effects of practice application are satisfactory. It will give a beneficial reference to other analogical mine and has an extensive application prospect.
文摘Based on the equation of the gas flow continuity and state, Darcy law and Langmuir equation, the law of methane seepage in the wall of drainage roadway was studied. The governing equation of methane one-way seepage in the seam was founded. By solving the equation, the calculation of methane seepage velocity in the coal wall was worked out. The result has really applied worth and will give beneficial references to re-lated research, it provides preventing coal and gas outbursts with theoretical gist.
文摘On the basis of that rock material usually has a larger fracture process zone,a new fracture criterion which is different from that of linear elastic fracture theory was presented.On this basis,the fracture behavior and influencing factors under modeⅡor compressive shear loading were investigated.
文摘The Chinese coastal regions are the high risk areas of natural disasters for their lowland and weak and sensitive eco-evironment. The relative sea-level rising (RSLR), resulting from the piling of global sea-level rising and regional land subsidence, is to speed up in the 21st century. Certainly the RSLR will exacerbate the land submerging, the disaster from storm-tide and flood-waterlogging and the water shortage, and then affect urban withstanding function, construction safety and eco-resources. According to sustainable development theory, the sustainable utilization of resources and environment and sustainable development of economy and society can both be effectively achieved in coastal regions of China in the 21st century only by the implementation of controlling discharge of greenhouse gas, optimal exploitation of and artificial recharge of ground-water, systematic control of land subsidence, higher design standards for tide and flood controlengineering, improving urban anti-disaster ability, a study on strategy and policy for RSLR and establishment of forecast and pre-warning institution.
