为建立地表移动的概率积分法计算参数与地质采矿条件之间的数学关系,以我国主要矿区的大量地表移动观测站实测数据为原始数据,采用逐步回归的方法建立了开采沉陷概率积分法参数与地质采矿条件之间的统计回归公式。采用中误差和威尔莫特...为建立地表移动的概率积分法计算参数与地质采矿条件之间的数学关系,以我国主要矿区的大量地表移动观测站实测数据为原始数据,采用逐步回归的方法建立了开采沉陷概率积分法参数与地质采矿条件之间的统计回归公式。采用中误差和威尔莫特一致性指数(WIA,Willmott’sIndex of Agreement)对回归公式的精度及预测能力进行评定,计算结果表明所建立的回归公式误差较小,各参数回归公式均具有较好的泛化性能。为进一步验证所建立的回归公式的正确性,以4个测试样本数据进行计算,计算结果与实测结果吻合。最后,以淮北某矿地表移动实测数据为例,计算结果表明采用统计规律所计算的概率积分法参数进行开采沉陷预计计算可以得到与实测相符的地表移动变形数据。研究成果为缺少实测资料矿区进行开采沉陷预测确定概率积分法参数提供了科学依据。展开更多
Damage caused by underground coal mining is a serious problem in mining areas in China; therefore, studying and obtaining the rules of ground movement and deformation under different geological conditions is of great ...Damage caused by underground coal mining is a serious problem in mining areas in China; therefore, studying and obtaining the rules of ground movement and deformation under different geological conditions is of great importance. The numerical software ANSYS was used in this study to simulate mining processes under two special geological conditions： （1） thick unconsolidated soil layer and thin bedrock; （2） thin soil layer and thick bedrock. The rules for ground movement and deformation for different soil layer to bedrock ratios were obtained. On the basis of these rules, a prediction parameter modified model of the influence function was proposed, which is suitable for different values of unconsolidated soil layer thickness. The prediction results were verified using two sets of typical field data.展开更多
Stress distribution rules and deformation and failure properties of coal and rockbodies influenced by mining were analyzed.Experimental research on permeability of coaland rock samples under different loading conditio...Stress distribution rules and deformation and failure properties of coal and rockbodies influenced by mining were analyzed.Experimental research on permeability of coaland rock samples under different loading conditions was finished in the laboratory.In-situmeasurement of coal permeability influenced by actual mining was done as well.Theoryanalysis show that permeability varied with damage development of coal and rock understress,and the influence of fissure on permeability was greatest.Laboratory results showthat under different loading conditions permeability was different and it varied with stress,which indicated that permeability was directly related to the loading process.In-situ testsshowed that permeability is related to abutment stress to some degree.The above resultsmay be referenced to gas prevention and drainage.展开更多
The numerical simulation of jet flow field in Laval tube was carried out first by commercial software CFX4.4, and it is used to determine inlet pressure condition out of nozzle in order to its numerical simulation. Th...The numerical simulation of jet flow field in Laval tube was carried out first by commercial software CFX4.4, and it is used to determine inlet pressure condition out of nozzle in order to its numerical simulation. The decay rule of jet middle line velocity of axial symmetry turbulence jet and cross section＇s expand situation out of the tube in different stagnation pressure and surrounding temperature were analyzed systematically. The result showed that K-e model is suitable for numerical simulation. The conclusion will have important guide and referent function to research of two important craft parameters, impact depth and the impact area which are related to steel-making production practice.展开更多
The variational principles for 1-D unsteady compressible flow in a deforming tube derived in a previous paper are improved essentially by reconstructing the initial/final-integral terms according to a new method sugge...The variational principles for 1-D unsteady compressible flow in a deforming tube derived in a previous paper are improved essentially by reconstructing the initial/final-integral terms according to a new method suggested in a recent paper. As a result, the inherent shortcoming of variational principles of being unable to admit physically rational initial/final-value conditions in initial/boundary-value problems is successfully eliminated. Thus, a new theoretical basis for the time-space finite-element analysis is provided.展开更多
文摘为建立地表移动的概率积分法计算参数与地质采矿条件之间的数学关系,以我国主要矿区的大量地表移动观测站实测数据为原始数据,采用逐步回归的方法建立了开采沉陷概率积分法参数与地质采矿条件之间的统计回归公式。采用中误差和威尔莫特一致性指数(WIA,Willmott’sIndex of Agreement)对回归公式的精度及预测能力进行评定,计算结果表明所建立的回归公式误差较小,各参数回归公式均具有较好的泛化性能。为进一步验证所建立的回归公式的正确性,以4个测试样本数据进行计算,计算结果与实测结果吻合。最后,以淮北某矿地表移动实测数据为例,计算结果表明采用统计规律所计算的概率积分法参数进行开采沉陷预计计算可以得到与实测相符的地表移动变形数据。研究成果为缺少实测资料矿区进行开采沉陷预测确定概率积分法参数提供了科学依据。
文摘Damage caused by underground coal mining is a serious problem in mining areas in China; therefore, studying and obtaining the rules of ground movement and deformation under different geological conditions is of great importance. The numerical software ANSYS was used in this study to simulate mining processes under two special geological conditions： （1） thick unconsolidated soil layer and thin bedrock; （2） thin soil layer and thick bedrock. The rules for ground movement and deformation for different soil layer to bedrock ratios were obtained. On the basis of these rules, a prediction parameter modified model of the influence function was proposed, which is suitable for different values of unconsolidated soil layer thickness. The prediction results were verified using two sets of typical field data.
基金Supported by the National Major Fundamental Research Program of China(973 Project)(2005CB221503)National Science Foundation of China(50544010)
文摘Stress distribution rules and deformation and failure properties of coal and rockbodies influenced by mining were analyzed.Experimental research on permeability of coaland rock samples under different loading conditions was finished in the laboratory.In-situmeasurement of coal permeability influenced by actual mining was done as well.Theoryanalysis show that permeability varied with damage development of coal and rock understress,and the influence of fissure on permeability was greatest.Laboratory results showthat under different loading conditions permeability was different and it varied with stress,which indicated that permeability was directly related to the loading process.In-situ testsshowed that permeability is related to abutment stress to some degree.The above resultsmay be referenced to gas prevention and drainage.
文摘The numerical simulation of jet flow field in Laval tube was carried out first by commercial software CFX4.4, and it is used to determine inlet pressure condition out of nozzle in order to its numerical simulation. The decay rule of jet middle line velocity of axial symmetry turbulence jet and cross section＇s expand situation out of the tube in different stagnation pressure and surrounding temperature were analyzed systematically. The result showed that K-e model is suitable for numerical simulation. The conclusion will have important guide and referent function to research of two important craft parameters, impact depth and the impact area which are related to steel-making production practice.
文摘The variational principles for 1-D unsteady compressible flow in a deforming tube derived in a previous paper are improved essentially by reconstructing the initial/final-integral terms according to a new method suggested in a recent paper. As a result, the inherent shortcoming of variational principles of being unable to admit physically rational initial/final-value conditions in initial/boundary-value problems is successfully eliminated. Thus, a new theoretical basis for the time-space finite-element analysis is provided.
