1、翻译部分英文原文Numerical Simulation of Coal Floor Fault Activation Influenced by Mining WANG Lian-guo,MIAO Xie-xingSchool of Sciences,China University of Mining&Technology,Xuzhou,Jiangsu 221008,ChinaAbstract:By means of the numerical simulation software ANSYS,the activation regularity of coal floor faults
2、caused by mining is simulated.The results indicate that the variation in horizontal,vertical and shear stresses,as well as the horizontal and vertical displacements in the upper and the lower fault blocks at the workface are almost identical.Influenced by mining of the floor rock,there are stress re
3、leasing and stress rising areas at the upper part and at the footwall of the fault.The distribution of stress is influenced by the fault so that the stress isolines are staggered by the fault face and the stress is focused on the rock seam around the two ends of the fault.But the influence in fault
4、activation on the upper or the lower fault blocks of the workface is markedly different.When the workface is on the footwall of the fault,there is a horizontal tension stress area on the upper part of the fault;when the workface is on the upper part of the fault,it has a horizontal compressive stres
5、s area on the lower fault block.When the workface is at the lower fault block,the maximum vertical displacement is 5 times larger then when the workface is on the upper fault block,which greatly increases the chance of a fatal inrush of water from the coal floor.Key words:mining;fault activation;sim
6、ulation1 IntroductionIn this paper we attempt to appraise the activation regularity and deformation of coal floor faults caused by mining.Damage mechanisms of rock around coal floor faults are described from different aspects and in different contexts110.Descriptions can,to some extent,intensify our
7、 understanding of coal floor fault activation caused by mining.However, looking at the effect of these views,a mechanical analysis cannot achieve the purpose of pictures and clarity.For a more profound understanding of the regularity of fault activation caused by mining at the workface,we use comput
8、ers to make numerical simulations and obtain a series of valuable conclusions. 2 Numerical Calculation of Model FormationConsidering the different fault activations influenced by the workface on the upper and lower fault blocks,we build two calculation models according to the state of the plane stra
9、in.Fig.1 is a calculation model(Model)of the workface on the lower fault block,showing the loading on the top of the terrane according to the distributional characteristics11 of mine pressure.Given the conditions of mining technology of the Qinan mine,the terrane 70 m fore- and-aft the workface and
10、30 m deep under the coal floor is simulated.The lithology of the floor is Berea sandstone and the elastic modulus E=1.09104MPa,the Poissons ratio=0.34,the cohesion C=2.94MPa,the internal friction angle=35 and the density=2.5 kN/m3.The calculation model of the workface on the upper part of the fault(
11、Model)is the same as that of Modelexcept that the abutment pressure ahead of the workface is on the upper part of the fault.3 Numerical Simulation Results and AnalysisFor both models,the isoline graphs of horizontal, vertical and shear stresses as well as the horizontal and vertical displacements of
12、 modelsandhave been calculated and are plotted respectively as Figs.23. 3.1 Distribution characteristics of horizontal stressesInfluenced by mining of the coal floor rock, there are horizontal stress releasing areas and rising areas at the upper part and at the footwall of the fault. The distributio
13、n of horizontal stresses is influenced by the fault and it is obvious that the stress isolines are staggered by the fault face and the stress is concentrated on the rock seam around the two ends of the fault. In model I,stress is concentrated at the shallow part of the orebody at the footwall of the
14、 fault.The horizontal stress is 6.410 MPa.The horizontal stress under the fault face is 3.14.9 MPa.The lower part of mined-out areas on the lower fault block releases pressure,and may even turn to tension stress of about 0.5 MPa.But in the deeper part,the horizontal stress turns to compressive stres
15、s and the value increases gradually. In model,the stress is concentrated at the lower part of the orebody on the lower fault block and the horizontal stress becomes 14.627.5 MPa.The horizontal stress under the fault face is 4.948.16 MPa.The lower part of the mined-out areas at the fault footwall rel
16、eases pressure;the horizontal stress is 4.94 MPa. 3.2 Distributional characteristics of vertical stressesThe distributions of vertical stresses are also influenced by faults.The stress isolines are staggered by the fault face.The stress is focused on the rock seam round the two ends of the fault. In model I,the stress is concentrated at the lower part of the orebody on the lower fault block.When the depth increases,the extent of the
