摘要：In this research, determination of final slope for Maiduk copper mine of Kerman is investigated according to destabilizing factors of the mine. The development of the Maiduk Mine caused the extension of the mine area and also withdrawal of its wall. So, optimizing possibility of mine slope is essential. Finally,the magnitude of optimized slopes for different walls of the mine in association with executive commands with better factors of safety is provided. The results show that the most important destabilizer factors are the presence of water and pore pressure in the faults and the main joints. With the omission of pore pressure, mine wall for the designed depth is quite stable. This requires a drainage pattern in the lifetime of the mine. In an optimistic point of view, the minimum factor of safety of the wall will be 2.81 even without drainage. This conclusion allows optimizing the slope to its maximum magnitude of 51 degree. With the pessimistic engineering judgment and with the higher SF, the magnitude of the slope is optimized to 47 degree.

摘要：Coal is the world's most abundant fossil *** froth flotation is a widely used cleaning process to separate coal from mineral *** of coarse coal particles,ultrafine coal particles and oxidized coal particles is well known to be difficult and *** this paper,the nanobubbles' effects on the flotation of the varying particle size,particle density and floatability coal samples were evaluated using a bank of pilot scale flotation cells,a laboratory scale and a pilot scale specially designed flotation *** parameters evaluated during this study include the flow rate ratio between the nanobubble generator and the conventional size bubble generator,the superficial air velocity,collector dosage,frother concentration,flotation feed rate,feed solids concentration,feed particle size,and the superficial wash water flow rate,*** results show that the use of nanobubbles in a bank of mechanical cells flotation and column flotation increased the flotation recovery by 8%～27% at a given product *** increased the flotation rate constants of 600～355,355～180,180～75,and 75～0 microns size coal particles by 98.0%,98.4%,50.0% and 41.6%,*** separation selectivity index was increased by up to 34%,depending on the flotation feed characteristics and the flotation conditions.

摘要：Surface mining operations extract a large quantity of waste material,which is generally disposed into a dump *** waste can cause a series of environmental problems ranging from landscape deterioration to acidic water generation and water ***,mine waste management is a significant task in mining *** known,in strip mining,the overburden is not transported to waste dumps but disposed directly into adjacent strip which was mined *** concept can be adapted for mine planning of relatively horizontal deposits through a mixed integer programming(MIP)*** main idea behind this work is that,in one pit,production voids created in early year of mining are used for waste landfilling in late years of *** other words,in addition to external dumping,a landfilling option within the same pit is proposed for mine design *** problem is formulated as maximization of the net present value(NPV)of the mining project under the constraints of access,landfill waste handling,mining and processing capacities.A case study using a data set was carried out to see the performance of the proposed *** findings showed that this approach could be used in waste management incorporating a landfilling option into mine *** a result,material handling costs decrease,and environmental compliance increases due to less external waste quantity.

摘要：Stope mining design is a very important and complicated task in daily production design and technical management of an underground *** on workface technology and human-computer interaction technology,this study introduces a method of 3D parametric design for the irregular structure of stope bottoms,and focuses on solving technical problems in surface modeling of stope bottom *** of the minimum span length algorithm(MSLA) and the shortest path search algorithm(SPSA) is conducted to solve the problem of contour-line based instant modeling of stope bottom structures,which makes possible the 3D parametric design for irregular structure of stope *** process and relevant methods of the proposed algorithms are also *** and reliability of the proposed modeling method are testified in a case *** practice,the proposed 3 D parameterization design method for irregular structure stope bottom proves to be very helpful to precise 3D parametric *** method is capable of contributing to improved efficiency and precision of stope design,and is worthy of promotion.

摘要：Taking a study area in Jinzhong Basin in Qixian County,Shanxi Province,as an example,this work performs an intelligent interpretation of ground *** the basis of a complete analysis of the regional geological background in the study area,dip-steering cube operation and median filtering of seismic data were performed using fast Fourier transform to improve the continuity of seismic events and eliminate random noise.A total of 200 stratigraphic continuous sample training points and 500 discontinuous training points were obtained from the processed seismic ***,a variety of attributes(coherence,curvature,amplitude,frequency,etc.)were extracted as the input for the multilayer perceptron neural network *** the training period,the training results were traced by normalized root mean square error(RMSE)and misclassifi *** training results showed a downward trend during the training *** misclassifi cation curve was stable at 0.3,and the normalized RMSE curve was stable at *** the value of the normalized RMSE curve reached the minimum,the training was terminated,and the training results were extended to the whole data volume to obtain the attribute cube of intelligent ground fi ssure *** characteristics of ground fi ssures were analyzed and identifi ed from the sections and slices.A total of 11 ground fissures were finally *** interpretation results showed that the dip angles were 60°-85°,the fault throws were 0-43 m,and the extension lengths were 300-1,100 m in the whole *** strike of 73%of the ground fi ssures was consistent with the direction of the regional tectonic *** cally,four ground fi ssures coincided with the surface disclosed,and the verifi cation rate reached 100%.In conclusion,the intelligent ground fi ssure detection attribute based on the dip-steering cube is eff ective in predicting the spatial distribution of ground fi ssures.

摘要：The problem of active vibration control for uncertain linear structural systems with control forces input timedelay is investigated in this ***,the original structural equation is converted to a state-space model by utilizing the matrix ***,according to the obtained model and a special Lyapunov functional,a sufficient condition is achieved for the closed-loop system to be stable with a prescribed level of disturbance ***,in terms of solving these linear matrix inequalities（LMIs）,the state-feed controller is achieved to stabilize the structural system with the performance ‖z‖2<γ‖ω‖***,by introducing the rank-1 vector to describe the system uncertainties,the uncertain system description is obtained,and the stabilizing condition is extended to the uncertain ***,examples are given to show the effectiveness of the proposed methods.

摘要：Most of the coal reservoirs in China are of low-permeability, so hydraulic fracturing is widely used to improve the per- meability in the extraction of gas by ground drilling. The ground stress around the well was analyzed by using theory of elasticity. The pressure when the well fractured is formulated and the effect of ground stress on pressure is discussed. The effect of ground-stress-differences on hydraulic fracturing was analyzed by using the numerical software RFPA2D-Flow in reference to the tectonic stress in Jincheng coal area. The results show that: 1) the position where initial fracture appears is random and fracture branches emerge when the fractures expand if ground stresses in any two directions within a horizontal plane are equal; 2) other- wise, the fractures expand in general along the direction of maximum ground stress and the critical pressure decreases with in- creasing ground-stress-differences and 3) the preferred well-disposition pattern is diamond shaped. The preferred well spacing is 250 m×300 m. This study can provide a reference for the design of wells.

摘要：为探究浅埋薄基岩超长工作面液压支架群组的承载特性,构建了工作面煤壁-支架-顶板的弹性基础梁力学模型,研究了7种因素对支架阻力的影响。理论计算与实测结果吻合良好。研究结果表明:支架工作阻力呈单峰值与“M”形三峰值两种分布形式;工作面长度、基本顶厚度和弹性模量影响支架阻力分布曲线形状和高阻力范围;采高和上覆岩层载荷影响曲线值;支架刚度影响高阻力范围;巷帮刚度影响靠近巷道侧的支架阻力。基于此,提出了包括确定适当面长、支架分区调控、煤壁协同控制、巷帮主动强化等手段在内的浅埋薄基岩超长工作面关键安全管控措施。研究成果可为浅埋薄基岩超长工作面支架阻力设计与灾害预防提供理论依据。

摘要：Aiming at soft rock ground support issues under conditions of high stress and long-term water immersion, the ground failure mechanism is revealed by taking the deep-water sumps of Jiulong Mine as the engineering background and employing field investigation, tests of rock structure, mechanical properties and mineral composition. The main factors leading to the surrounding rock failure include the high and complex stress state of the water sumps, high-clay content and water-weakened rock, and the unreasonable support design. In this paper, the broken and fractured rock mass near roadway opening is considered as ground small-structure, and deep stable rock mass as ground large-structure. A support technology focusing on cutting off the water, strengthening the small structure of the rock and transferring the large structure of the rock is proposed. The proposed support technology of interconnecting the large and small structures, based on high-strength bolts, high-stiffness shotcrete layer plugging water,strengthening the small structure with deep-hole grouting and shallow-hole grouting, highpretensioned cables tensioned twice to make the large and small structures bearing the pressure evenly,channel-steel and high-pretensioned cables are used to control floor heave. The numerical simulation and field test show that this support system can control the rock deformation of the water sumps and provide technical support to similar roadway support designs.

摘要：Experimental study was carried out on the in-plane bending behavior of glass plates without lateral supports, and the effects of the factors, such as height-to-span ratio, on the stability of glass panels were studied. Results show that the in-plane bending glass plates with both ends simply supported and their upper edge free lose overall stability under loads, which belongs to the limit-point type of instability. It is found that the buckling load increases linearly with the increase of height-to-span ratio of the glass plates. The lateral stress of in-plane bending glass plates without lateral supports increases linearly under loads; while the large-area stress increases nonlinearly and the lateral stress is not the controlling factor of instability. In finite element analysis, the first buckling mode is regarded as the initial imperfection and imposed on the model as 1/1000 of the span of the components. The numerical buckling load according to the theory of large deflection is less than the experiment result, which is more conservative and can provide some reference for design. For the design method, when the in-plane load is imposed on the glass plate, its lateral strength and the deflection should be verified. Considering the stability of the in-plane bending glass plate without reliable lateral support, buckling is another possible failure mode and calls for verification.