Advanced Materials Research Vols. 734-737

Abstract: Mechanical and deformation characteristics of pile-anchor retaining structure was analyzed by using numerical simulation method. The rationality of numerical model was also verified through comparing measured data in field test and numerical results. On the basis of this numerical model, Mechanical and deformation characteristics of pile-anchor retaining structure under three different construction procedures were analyzed individually. The results show that: the maximum horizontal displacement of pile is controlled effectively by applying anchoring force, and the global horizontal displacement of pile increases as well. Forced state of pile is changed from being bended on one side to being bended on both sides, and maximum moment value decreases heavily. Therefore, anchor cable reinforcement should be arranged at the head of construction procedure of pile-anchor retaining structure. The later anchoring force be applied, the closer inflection point nears the pile top.

Abstract: Mine ventilation simulation system is a set of advanced, reliable and practical ventilation simulation system, which has a function of ventilation system simulation and visualization. It solved the technical problems such as automatic establishment and management of the topological relations, automatic identification of diagonal connection and air distribution according to demand under fixed cut set. According to the complexity of ChenSiLou coal mine ventilation system, the detailed analysis research is carried on. Mine ventilation simulation system has a successful connection with the mine monitoring system, realizing the real-time monitoring and real-time query. The technology is taken to optimize and transform the ventilation system of the mine. To ensure that the optimization and transformation of the ventilation system of the mine are carried out successfully, it simulated the ventilation system reconstruction scheme of the mine .The final plan is determined and has obtained the good effect of field application.

Abstract: The complex construction behavior inevitably disturb surrounding environment, even when the tunneling goes through building, which may be wrecked. The security issues of the subway project stems from ground movement and structure dynamic interaction. So it is academic and application good value for study on construction influences of shield tunnel excavation to the neighboring buildings. This paper focuses on the shield tunnel construction strata deformation factors. The results provided the theory basis for safety construction.

Abstract: According to the characteristics of the island workface with hard roof, various mechanical models of hard roof in island workface are established, to analyze energy characteristics of hard roof before and after the first fracture in island workface with all round gobs, derived their simplified formulas of bending strain energy for hard roof before and after the first fracture, and using these formulas to estimate the bending strain energy for the typical case of coal bump, reveals the energy cause of coal bump and verify the validity of these formulas.

Abstract: This paper designs a square column leaching experiment to probe the coupling flow-reaction-transmission. 2.372 kg of Yanglas copper ore with a grade of 1.25% was loaded in a 6×6 cm² column whose height is 60 cm. A 28-day leaching gave an approximate copper yield of 14.5 gram, which is an equivalence of copper leaching rate being 50%. Hydraulic conductivity was measured. The changing trends are analyzed by mathematical analysis software Eviews and Matlab, and the numerical simulation was conducted.

Abstract: Experiments on coal permeability with saturated water under tri-axial stress were conducted. The relationship between stress and permeability under tri-axial stress was analyzed on the rock mechanical experimental rig (GAW-2000). After the experiments on permeability, the fracture characteristics were researched by X-ray computerized tomography, which shows that the bituminous coal normally has high fractal dimensions (generally over 1.8) and wide aperture. The results for permeability reveal that bituminous coals always have variable permeability characteristics under incremental axial stress due to its inherent fracture features. It can be divided into two types: type I, at the linear and nonlinear elastic deformation and peak stage, the permeability keeps rising, which is represented by FYGY8 #. The main control factor of permeability should be related to coal microfractures and coal compositions. Type II, which is represented by sample YCLZ2#, in the initial linear elastic stage, there is a decrease trend in the permeability performance, and then permeability gradually rise when it comes into the stage of nonlinear elastic deformation. The permeability will keep go down after coal becomes soften under the action of confining pressure, compaction.

Abstract: With the continued growth in demand for mineral resources, various countries have begun to emphasize the efficiency of the development and utilization of mineral resources, mining management system of a country becomes a research hotspot. Administrative agencies are always part of this system. The United States is one of the big countries of the mineral resources and has accumulated a wealth of experience to the development and management of mineral resources since the promulgation of the Mining Act (1872).The study of its mining administrative agencies will become a reference to China's mining management and department reform. First, this article will introduce current mining administrative agencies of the United States. Secondly, it will summarize the experience of the U.S. mining management. Finally, it will propose to think on the China's mining management.

Abstract: With the increase of mining intensity, mining causes significant dynamic disturbance and dynamic disasters, which have exerted a great influence on the safety and high-efficiency of production. This article based on the study of the displacement tendency of the rock masses on or under fractured face of the key layer, deduces the vertical stress calculation formula of the rock mass under the fractured face which indicates that the vertical stress is correlative with the length of fault block in key layer, the depth of key layer, the distance between key layer and mining coal seam, the equivalent elastic modulus of coal stratum underlying the key layer and so on; And then by numerical simulation, it studies the dynamic disturbance effect on front coal-rock masses as the key layer fractures which shows that dynamic disturbance effect caused by high intensity mining is relatively conspicuous on the fractured stratum (the key layer), the stratum under the fractured one and the stratum in the advancing direction of working face; As for the stratum on the fractured one (the key layer),the dynamic disturbance effect becomes less conspicuous as they grow farther away from the fractured one.

Abstract: As we all know, a large number of waste rock which caused many serious problem produced in mining. The pollution caused by waste rock in mining is threating the human society seriously in some aspects. Wasteless mining is more and more popular to relieve the burden of mines. As one of the deepest mines in China, Hongtoushan Copper Mine began to establish waste rock filling system in 1995. After three phases of the waste rock filling system, all the waste rock was used to fill the goaf in underground mining in 2012. The wasteless rock mining had brought RMB 8 million and good social benefits. It offered a good suggestion for similar mines in China.

Abstract: The metal mine ventilation system is a complex system composed of interactive factors. To get a relative impersonal assessment result of the metal mine ventilation system, the issues, network optimization and program optimization, were discussed and the fuzzy optimization of metal min ventilation system was presented in this paper. Based on the two classic nonlinear programming models for mine ventilation networks, the mathematical model of fuzzy optimization for mine ventilation networks was put forward. A algorithm principle is provided for solving the superior support in a quicker and easier way.