The filling mining method is important in realizing the green mining of mineral resources.Aiming at the problems of land resource occupation,environmental pollution,and rational utilization of coal-based solid wastes ...The filling mining method is important in realizing the green mining of mineral resources.Aiming at the problems of land resource occupation,environmental pollution,and rational utilization of coal-based solid wastes such as coal gangue,fly ash,and desulfurization gypsum,a new paste filling material was developed with coal gangue,fly ash,and desulfurization gypsum as raw materials.The microstructure of the raw materials was analyzed by XRD and SEM.Combined with the Box-Behnken experimental design,the effect of each component on the fluidity of the filling slurry was analyzed through the response surface analysis.The significance of each component on its bleeding and fluidity was determined,and the optimal ratio of the filling slurry was obtained.Experimental results show that the microcosmic morphology of coal gangue,desulfurization gypsum,and gasification slag presents an irregular block and rough particle surface;the microcosmic morphology of fly ash and bottom slag presents first out spherical or quasi spherical particles.Moreover,obvious sintering traces exist on the surface of the bottom slag.The main crystal mineral of coal gangue and fly ash is SiO_(2),the desulfurization gypsum is composed of Ca(SO_(4))(H_(2)O)and Ca(CO_(3))crystal minerals,the gasification slag is composed of carbon and nitrogen compounds,and the main crystal mineral components in the bottom slag sample are SiO_(2) and Al_(x)Si_(y)O_(z) compounds.The order of significance of each key factor on slurry fluidity is as follows:C(desulfurization gypsum)>D(gasification slag and bottom slag 1:1)>A(coal gangue)>B(fly ash).The order of the significance of each key factor on slurry bleeding is as follows:B(fly ash)>C(desulfurization gypsum)>D(gasification slag and bottom slag 1:1)>A(coal gangue).Considering the material preparation,field application,and other conditions,the mass percentage of each factor content of the new paste filling material is as follows:49.5%coal gangue,8.3%fly ash,4.1%desulfurization gypsum,6.2%gasification slag,and 6.2%bottom slag.展开更多
The motion forms（deformation） of the sliding soil along the slope include inviscid particle flow,viscous particle flow,and mass sliding.The motion forms were mainly influenced by the mechanical properties of the vis...The motion forms（deformation） of the sliding soil along the slope include inviscid particle flow,viscous particle flow,and mass sliding.The motion forms were mainly influenced by the mechanical properties of the viscous mud medium filling.The effect of the medium filling on the motion forms of the sliding soil is worth discussing.The sliding soil can be seen as the mixture which is composed of the medium filling and coarse particles.The Chengdu clay with different moisture contents were selected as the medium filling.Their mechanical parameters were experimentally measured for simulating the moving process of the sliding soil.Different motion forms of the sliding soil were numerical simulated based on PFC3D by changing the specific mechanical parameters.The mechanical parameters of the Chengdu clay are experimentally determined.The numerical results show that with the moisture content of the filling slurry medium in the range of 〉302%,101%~182%,and 〈80%,the motion form of the sliding soil belongs to the inviscid particles flow（similar with the sliding sand）,viscous particles flow（seen as the viscous flows）;and masssliding（seen as the block sliding along the slope surface）,respectively.展开更多
基金We acknowledge the financial support for this work provided by the National Natural Science Foundation of China(Grant No.51774010)National Key R&D Program of China(Grant No.2019YF1904304).
文摘The filling mining method is important in realizing the green mining of mineral resources.Aiming at the problems of land resource occupation,environmental pollution,and rational utilization of coal-based solid wastes such as coal gangue,fly ash,and desulfurization gypsum,a new paste filling material was developed with coal gangue,fly ash,and desulfurization gypsum as raw materials.The microstructure of the raw materials was analyzed by XRD and SEM.Combined with the Box-Behnken experimental design,the effect of each component on the fluidity of the filling slurry was analyzed through the response surface analysis.The significance of each component on its bleeding and fluidity was determined,and the optimal ratio of the filling slurry was obtained.Experimental results show that the microcosmic morphology of coal gangue,desulfurization gypsum,and gasification slag presents an irregular block and rough particle surface;the microcosmic morphology of fly ash and bottom slag presents first out spherical or quasi spherical particles.Moreover,obvious sintering traces exist on the surface of the bottom slag.The main crystal mineral of coal gangue and fly ash is SiO_(2),the desulfurization gypsum is composed of Ca(SO_(4))(H_(2)O)and Ca(CO_(3))crystal minerals,the gasification slag is composed of carbon and nitrogen compounds,and the main crystal mineral components in the bottom slag sample are SiO_(2) and Al_(x)Si_(y)O_(z) compounds.The order of significance of each key factor on slurry fluidity is as follows:C(desulfurization gypsum)>D(gasification slag and bottom slag 1:1)>A(coal gangue)>B(fly ash).The order of the significance of each key factor on slurry bleeding is as follows:B(fly ash)>C(desulfurization gypsum)>D(gasification slag and bottom slag 1:1)>A(coal gangue).Considering the material preparation,field application,and other conditions,the mass percentage of each factor content of the new paste filling material is as follows:49.5%coal gangue,8.3%fly ash,4.1%desulfurization gypsum,6.2%gasification slag,and 6.2%bottom slag.
基金provided by National Natural Science Foundation(Grant No.41372331)the international cooperation project of Ministry of Science and Technology(Grant No.2013DFA21720)Key Laboratory of Mountain Hazards and Earth Surface Processes independent project funding:Dynamic process and buried risk of debris flow in Shenxi gully after Wenchuan earthquake
文摘The motion forms（deformation） of the sliding soil along the slope include inviscid particle flow,viscous particle flow,and mass sliding.The motion forms were mainly influenced by the mechanical properties of the viscous mud medium filling.The effect of the medium filling on the motion forms of the sliding soil is worth discussing.The sliding soil can be seen as the mixture which is composed of the medium filling and coarse particles.The Chengdu clay with different moisture contents were selected as the medium filling.Their mechanical parameters were experimentally measured for simulating the moving process of the sliding soil.Different motion forms of the sliding soil were numerical simulated based on PFC3D by changing the specific mechanical parameters.The mechanical parameters of the Chengdu clay are experimentally determined.The numerical results show that with the moisture content of the filling slurry medium in the range of 〉302%,101%~182%,and 〈80%,the motion form of the sliding soil belongs to the inviscid particles flow（similar with the sliding sand）,viscous particles flow（seen as the viscous flows）;and masssliding（seen as the block sliding along the slope surface）,respectively.
