摘要：Cibaliung Underground Gold Mine applies cut and fill mining method to optimize ore production and maintain underground stability. Existing 5 m × 5 m height and width of stope geometry has a potential new design to increase production of gold due to variety of thick ore, however serious shotcrete failures often occur in hanging wall decline. This paper aims to find out the relationship between stope design and stability of hanging wall decline. The analysis conducted in this study is based on underground characteristics and geological condition of Cibaliung area. The impact of stope design on decline stability was analyzed by using numerical methods. The impact factors such as different rock mass, size of stope, and distance between stope and hanging wall decline were used in the analysis of underground stability especially stability on hanging wall decline.

摘要：For tunnels being excavated through multiple knowledge of the aquifers’hydraulic head becomes essential for determining groundwater inflow into the tunnel and analyzing its stability,specifically using multilevel monitoring *** the multi-aquifer alluvial section of the Glas tunnel(Iran),since the hydraulic head calculations were based on the data obtained from single-piezometer boreholes,the excavation risk was assessed to be at high level and the tunnel seemed to be unstable,thus an incorrect conclusion was derived from the misleading *** take cost mitigation measures into account,it was necessary to calculate the hydraulic head at tunnel level *** installing nested and clustered wells the mean hydraulic head was measured to be 70 m,significantly different from the 90 m previously determined by *** the updated value,the groundwater inflow and bulkhead load,formerly calculated as 0.65 m^(3)/s and 9.5 bars,were determined to be 0.49 m^(3)/s and 7.5 bars,respectively.

摘要：Non-pillar mining technology with automatically formed roadway is a new mining method without coal pillar reservation and roadway *** stability control of automatically formed roadway is the key to the successful application of the new *** order to realize the stability control of the roadway surrounding rock,the mechanical model of the roof and rib support structure is established,and the influence mechanism of the automatically formed roadway parameters on the compound force is *** this basis,the roof and rib support structure technology of confined lightweight concrete is proposed,and its mechanical tests under different eccentricity are carried *** results show that the bearing capacity of confined lightweight concrete specimens is basically the same as that of ordinary confined concrete *** bearing capacity of confined lightweight concrete specimens under different eccentricities is 1.95 times higher than those of U-shaped steel *** comparing the test results with the theoretical calculated results of the confined concrete,the calculation method of the bearing capacity for the confined lightweight concrete structure is *** design method of confined lightweight concrete support structure is established,and is successfully applied in the extra-large mine,Ningtiaota Coal Mine,China.

摘要：Unexpected, serious deformation failures have occurred during construction of a main shaft. A study of construction parameters of the main shaft is required. First, the stability of the shaft and wall-rock is investigated by numerical methods. The modeling results are as follows： The convergence of shaft liner is greater than 60 mm at a depth of 650 m; the maximum principal stress in the liner approaches 190 MPa, which exceeds the strength of the liner, so it is inevitable that the liner deform locally. Second, stability analysis of shafts with different liner thicknesses has been completed. The results have the following features： If the depth where the liner thickness is increases from 400 mm to 500 mm is 650 meters, the convergence deformation of the liner is reduced by 3.4 mm while the maximum principal stress is reduced by 5 MPa. At a depth of 250 m if the liner thickness is increased from 400 mm to 500 mm the convergence of the liner is reduced by 1.5 mm while the maximum principal stress is reduced by 10 MPa. Therefore, increasing the liner thickness has little effect on liner convergence but can reduce the maximum principal stress in the liner. The thickness of the liner can be increased to reduce the maximum principal stress and increase the capacity for shear deformation. Finally, construction techniques employing releasing-displacements have been numerically simulated. The conclusions are that as the releasing displacement is increased the convergence of the surrounding rock increases linearly while the convergence of the lining decreases linearly. The plastic zone in the surrounding rock mass at first increases linearly but then, at a release-displacement of 95 ram, expands rapidly. These conclusions show that use of suitable releasing displacement can increase the self-supporting capacity of the surrounding rock. But when the releasing displacement exceeds 95 nun the plastic zone rapidly enlarges and stability rapidly decreases. The maximum principal st

摘要：Constructing the 3D virtual scene of a coal mine is the objective requirement for modernizing and processing information on coal mining production. It is also the key technology to establish a ＂digital mine＂. By exploring current worldwide research, software and hardware tools and application demands, combined with the case study site （the Dazhuang mine of Pingdingshan coal group）, an approach for 3D geo-visualization of a mine surface plant and mine roadway is deeply discussed. In this study, the rapid modeling method for a large range virtual scene based on Arc/Info and SiteBuilder3D is studied, and automatic generation of a 3D scene from a 2D scene is realized. Such an automatic method which can convert mine roadway systems from 2D to 3D is realized for the Dazhuang mine. Some relevant application questions are studied, including attribute query, coordinate query, distance measure, collision detection and the dynamic interaction between 2D and 3D virtual scenes in the virtual scene of a mine surface plant and mine roadway. A prototype system is designed and developed.

摘要：With the invention of coronary stent, promising clinical outcomes appeared. However, the long-term success of stent has been beaten by significant in-stent restenosis and consequently stents fractures (SF). Cardiologists have been looking on SF as a threat to patients’ life because it is associated with short- and possibly long-term morbidity rate. In this review, stent materials and properties from the perspective of materials engineering and clinical drivers are discussed. The review also outlines how stent materials and design have evolved with time. Opinions are given as to the merit and direction of various on-going and future developments.

摘要：A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced during the tunnel *** mitigate this problem,a support system was designed incorporating negative Poisson ratio(NPR)anchor cables with negative Poisson ratio *** model experiments,field experiments,and numerical simulation experiments were conducted to investigate the compensation mechanical behavior of NPR anchor *** large deformations of soft rocks in the Daliangshan Tunnel are caused by a high ground stress,a high degree of joint fracture development,and a high degree of surrounding rock fragmentation.A compensation mechanics support system combining long and short NPR anchor cables was suggested to provide sufficient counter-support force(approximately 350 kN)for the surrounding rock inside the *** the NPR anchor cable support system with the original support system used in the Daliangshan tunnel showed that an NPR anchor cable support system,combining cables of 6.3 m and 10.3 m in length,effectively prevented convergence of surrounding rock deformation,and the integrated settlement convergence value remained below 300 *** study provides an effective scientific basis for resolving large deformation problems in deeply buried soft rocks in western transverse mountain areas.

摘要：The vibrating string pressure sensor is designed according to the working surroundings and conditions. this sensor is used for the weighing of the fixed-quantity bucket loader in the main shaft lifting systems of coal mines. The design of the sensor has been introduced in detail. Calibrations and errors of the sensor theoretical fornada have also been analyzed.

摘要：A novel architectural Ti composite composed of network-woven structured TiB nanowires in a core-shell structured Ti matrix was fabricated to improve the strength of Ti matrix composites(TMCs),where the shell consists of rich N solute atoms while the core is deficient of N solute atoms through spark plasma sintering of powder mixtures of Ti powder and BN *** phase composition,morphology,element distribution,and mechanical properties of prepared samples were analyzed by X-ray diffraction(XRD),scanning electron microscope(SEM),electron probe microanalyzer(EPMA),and electronic universal material testing *** results indicate that the TMCs with designed architectures have been successfully achieved,and the as-prepared Ti-2BN(wt.%)composite exhibits an ultimate compressive strength of~1.8 GPa with a strain-to-fracture of~9%,while the Ti-1BN(wt.%)attains an ultimate compressive strength of~1.6 GPa and a strain-to-fracture of~20%.Moreover,the roles of the hybrid reinforcement structures in strengthening the Ti composites were discussed.

摘要：矸石胶结充填开采是一种重要的充填开采方法,然而,酸性矿井水会严重影响矸石胶结充填体的强度。在本研究中,将矸石胶结充填体试件分别置于不同环境(空气、水、硫酸溶液、硫酸与荷载耦合)中,测试了不同龄期试件的抗压强度、电阻率及超声波波速,监测了加载过程中试件的声发射能量数值,同时结合扫描电镜和X衍射分析不同龄期充填体的微观结构。结果表明,1)空气中与水中养护的充填体抗压强度的增长趋势随龄期的增加而逐渐减缓。硫酸溶液中的充填体强度在前90天大于空气及水中养护的充填体强度。硫酸溶液与荷载耦合作用下充填体的强度随龄期的下降速率比单一硫酸溶液作用的较为缓慢;2)不同龄期矸石胶结充填体电阻率与超声波波速与强度有较好的对应关系。受侵蚀后矸石胶结充填体的破坏形式较为多样,且在加载不同阶段表现出不同的声发射能量特征,可以将声发射能量激增作为充填体的破坏前兆;3)侵蚀产物前期填充充填体内部孔隙,提高了其强度,后期会导致充填体膨胀开裂,强度降低。施加40%应力强度比的荷载会抵抗硫酸溶液的侵蚀。本文研究结果可以为充填体的耐侵蚀设计提供参考。