To solve the problem of water seepage of vertical feeding borehole for solid materials,we established the fluid-solid coupling dynamic model of groundwater flowing in rock mass adjacent to the vertical feeding borehol...To solve the problem of water seepage of vertical feeding borehole for solid materials,we established the fluid-solid coupling dynamic model of groundwater flowing in rock mass adjacent to the vertical feeding borehole.Combining with the engineering geological conditions,we built a numeral model to study the influence rule of the aquifer hydraulic pressure and seepage location of feeding borehole on the amount of seepage with fnite element numerical method.The results show that the nonlinear relationship is presented among the amount of seepage,the seepage location and aquifer hydraulic pressure.The higher the aquifer hydraulic pressure is,the closer the distance between seepage location and aquifer is,and the faster the harmful levels of aquifer will grow.In practice,we calculated the allowable seepage of feeding borehole by the optimum moisture content and natural moisture content of backflling materials,and then determined the protection zone of feeding borehole,so the moisture content of backflling materials can be controlled within the scope of optimum moisture content.展开更多
Based on the characteristics of surrounding rocks for deeply inclined roadway affected by argillation and water seepage, a structure model of layer crack plate was established to analyze the shear sliding instability ...Based on the characteristics of surrounding rocks for deeply inclined roadway affected by argillation and water seepage, a structure model of layer crack plate was established to analyze the shear sliding instability mechanism. Through solid mechanics analysis of anchored surrounding rock with defect from water seepage, combined with numerical analysis for instability mechanism under water seepage in deeply inclined roadway, key factors were proposed. Results show that with increasing height of layer crack plate, lateral buckling critical load value for high wall of the roadway decreases; there is a multistage distribution for tensile stress along the anchor bolt with defect under pulling state condition;groundwater seepage seriously affects the strength of surrounding rock of the roadway, to some extent the plastic zone of the high side rises up to 8 m. Finally some support strategies were proposed for the inclined roadway and successfully applied to Haoyuan coal mine in Tiela mining area,western China.展开更多
Tight sandstone gas(hereafter"tight gas")has become a subject of unconventional gas exploration globally.The large-scale development and use of tight gas resources in the USA,in particular,facilitated the ra...Tight sandstone gas(hereafter"tight gas")has become a subject of unconventional gas exploration globally.The large-scale development and use of tight gas resources in the USA,in particular,facilitated the rapid rebound of natural gas production in the USA,in addition to driving the rapid development of tight gas worldwide.In the eastern Ordos Basin,the Upper Paleozoic feature includes multiple layers of gas,a shallow depth,and notable potential for exploration and development.However,the reservoirs in the area are relatively tight,exhibit strong heterogeneity,and possess a complex micropore structure,thus restricting the eff ective economic development of oil and gas.Thus,research on the primary parameters controlling pore throat structure and the seepage capability of low-permeability reservoirs will be beneficial for the effcient exploration and development of natural gas in the eastern Ordos Basin.The parameters of reservoir porosity and percolation ability,as well as permeability,were analyzed using systematic sampling of the of the Upper Paleozoic Benxi,Taiyuan,and Shanxi Formations in the eastern Ordos Basin,constant-rate mercury injection experiments,nuclear magnetic resonance analysis,and gas–water-phase experimental studies.The results indicate that reservoir porosity is controlled by the effective pore volume and number,whereas permeability is controlled by the largest throat radius,rather than the average.The effective pore volume controls the movable fluid saturation,while reservoir percolation capability is controlled by the effective pore volume,irreducible water saturation,and size of the gas–water two-phase seepage zone.展开更多
基金funded by the State Key Development Program for Basic Research of China(No.2013CB227900)the National High Technology Joint Research Program of China(No.2012BAB13B00)
文摘To solve the problem of water seepage of vertical feeding borehole for solid materials,we established the fluid-solid coupling dynamic model of groundwater flowing in rock mass adjacent to the vertical feeding borehole.Combining with the engineering geological conditions,we built a numeral model to study the influence rule of the aquifer hydraulic pressure and seepage location of feeding borehole on the amount of seepage with fnite element numerical method.The results show that the nonlinear relationship is presented among the amount of seepage,the seepage location and aquifer hydraulic pressure.The higher the aquifer hydraulic pressure is,the closer the distance between seepage location and aquifer is,and the faster the harmful levels of aquifer will grow.In practice,we calculated the allowable seepage of feeding borehole by the optimum moisture content and natural moisture content of backflling materials,and then determined the protection zone of feeding borehole,so the moisture content of backflling materials can be controlled within the scope of optimum moisture content.
基金provided by the Natural Science Foundation of Jiangsu Province(No.BK20141130)the Fundamental Research Funds for the Central Universities(Nos.2014QNB27 and 2010QNB22)
文摘Based on the characteristics of surrounding rocks for deeply inclined roadway affected by argillation and water seepage, a structure model of layer crack plate was established to analyze the shear sliding instability mechanism. Through solid mechanics analysis of anchored surrounding rock with defect from water seepage, combined with numerical analysis for instability mechanism under water seepage in deeply inclined roadway, key factors were proposed. Results show that with increasing height of layer crack plate, lateral buckling critical load value for high wall of the roadway decreases; there is a multistage distribution for tensile stress along the anchor bolt with defect under pulling state condition;groundwater seepage seriously affects the strength of surrounding rock of the roadway, to some extent the plastic zone of the high side rises up to 8 m. Finally some support strategies were proposed for the inclined roadway and successfully applied to Haoyuan coal mine in Tiela mining area,western China.
基金supported by the National Natural Science Foundation of China(Grants Nos.41390451 and 41172101)the National Key Research Project of China(No.2016YFC0601003)
文摘Tight sandstone gas(hereafter"tight gas")has become a subject of unconventional gas exploration globally.The large-scale development and use of tight gas resources in the USA,in particular,facilitated the rapid rebound of natural gas production in the USA,in addition to driving the rapid development of tight gas worldwide.In the eastern Ordos Basin,the Upper Paleozoic feature includes multiple layers of gas,a shallow depth,and notable potential for exploration and development.However,the reservoirs in the area are relatively tight,exhibit strong heterogeneity,and possess a complex micropore structure,thus restricting the eff ective economic development of oil and gas.Thus,research on the primary parameters controlling pore throat structure and the seepage capability of low-permeability reservoirs will be beneficial for the effcient exploration and development of natural gas in the eastern Ordos Basin.The parameters of reservoir porosity and percolation ability,as well as permeability,were analyzed using systematic sampling of the of the Upper Paleozoic Benxi,Taiyuan,and Shanxi Formations in the eastern Ordos Basin,constant-rate mercury injection experiments,nuclear magnetic resonance analysis,and gas–water-phase experimental studies.The results indicate that reservoir porosity is controlled by the effective pore volume and number,whereas permeability is controlled by the largest throat radius,rather than the average.The effective pore volume controls the movable fluid saturation,while reservoir percolation capability is controlled by the effective pore volume,irreducible water saturation,and size of the gas–water two-phase seepage zone.
