Applied Mechanics and Materials Vols. 457-458

Abstract: The cable support system in large cross-section cable tunnel, which can solve the cable laying problem of big cross section cable and multi-loop cable effectively, gradually become the development trend of urban electricity transmission. Combined with the structure feature of large cross section shield tunnel, a new type of self-balanced shield tunnel cable support system is proposed. The safety and rationality of this system has been validated by the structure calculation, the finite element analysis of ADINA and the full scale model test. The analysis shows that the system has some advantages, such as excellent whole mechanical characteristics, strong adaptability, convenient construction and low cost. The system can fully satisfy all requirements of the cable tunnel construction and all functions of operation. The stress distribution of the structure is relatively homogeneous, the bearing capacity of components and the global stability of it also meet the requirements. With the test load which is about 1.5 ~ 4.0 times as large as design load, the support system displacement is 0.65 ~ 2.5 mm, which shows that the structure is safe and reliable. The research achievements can provide theoretical basis and experimental basis for the design of large cross-section cable tunnel.

Abstract: According to the basic idea of the finite element method, using the finite element software ANSYS to establish the finite element model of the reinforcement FRP pipe concrete under axial compression, introducing the unit selection in the process of building model ,based on the principle of meshing boundary conditions and constitutive relations selected; The significant degree of the model verified by compare with the test results. Analyzed by finite element reinforcement ratio, concrete strength and other factors on the mechanical properties of concrete under axial compression reinforcement FRP pipe, the analysis of the results shows: The increase of reinforcement ratio to improve the point load of the specimens and improve the composite column ultimate bearing capacity, but the reinforcement ratio increase will reduce the binding effect of the FRP pipe; The whole component be improved the strength of concrete can improve the ultimate bearing capacity, but it reduces the mechanical properties of the specimens.

Abstract: A new shaped charge annular cutter structure is put forward, and the process of annular jet formation and penetration into double plates is simulated by using ANSYS/LS-DYNA software. The kinematic characteristic of annular jet in the air is analysed. The damage effect on the plates is got. The simulation results show that an intilted phenomenon exists on the forming process of annual jet, and the annular jet is stretched into several annular penetrators after penetrating the upper plate. The annular jet formed by annular cutter shaped charge in the paper can realize effective penetration into double plates, and the results can provide reference for the design of tandem warhead front shaped charge.

Abstract: To avoid the precision decrease of the machining data transferred from CAD to rapid prototyping (RP) system, key techniques of driving RP machine within CAD system were researched. The method of achieving the layers contour scanning data within CAD system was researched; then, the direct driving mode of RP machine was established; finally, tests were conducted on a polystyrene foam cutter machine with example of layer generation. Tests show that the approximate processing to CAD model can be avoided between CAD and RP, and RP machine can be driven and controlled within CAD system.

Abstract: In the operation of the hydropower units, it often come across condition changes such as start-up, normal stop, increase or decrease the load and load rejection. This will cause the hydraulic transient process of the water power generation system, which is of great significance to the safe and stable operation of hydropower station. This paper analyzes the method to calculate the transient process of hydropower unit and expounds the principle of all kinds of calculation methods and steps to lay a foundation for further optimization study.

Abstract: The conventional dynamometer diagram diagnosis method of rod pumped well has the function to calculate the well yield based on the downhole dynagraph. In recent years, it can substitute for the traditional separator metering mode technically through further development and support to measure the oil well in an automatic and remote manner, analyze the working conditions and alarm in a real time manner, thus simplifying the collection process and improving the metering accuracy and working efficiency. In this paper, the technical and management problems in development and application of automatic metering technology of rod pumped well dynamometer diagram in Huabei Oilfield are discussed and solutions are proposed in order to guide the wide application of such technology in Huabei Oilfield.

Abstract: The emergency escape hatches of refuge cabin are usually installed in both sides of the life supporting compartment, which might cause the toxic gases or water enter into life supporting compartment when the gas explosion and water inrush accident occur. A new type of refuge cabin structure that can effectively resist the toxic gases and water entering the life supporting compartment is developed in this paper. Numerical simulation of antiknock impact performance of the new refuge cabin was calculated and analyzed by using the finite element software of LS-DYNA.The stress and strain distributions and maximum antiknock performance were obtained. Refuge chamber cabin has been optimized to reduce cost. The antiknock impact performance of optimized mine refuge chamber cabin can reach 1.4MPa which is greater than the 0.6MPa of standard value and the cost can be reduced approximate 19% than the original model.

Abstract: Electromagnet for valve is a key executive device of electromagnetic valve control system, as a dynamic element, force and displacement characteristics of electromagnet, directly affect the reliable performance of devices made of it. By reference to other electromagnet testing standard and method, proposed a based on vc6.0 and stepper motor of force and displacement characteristics for electromagnet test system. The system consists mechanical platform, pressure sensor, data acquisition card and PC test software. The system is easy to operate, high degree of automation, stable performance. Provides an auxiliary electromagnet selection testing and inspection tools, can improve the work efficiency.

Abstract: As information collection change with the events development in the situations of the emergency, a mathematical model is established on the basis of it, the emergency decision-makers take different measures at different times of emergencies is analyzed in detail to get the future demand for emergency resources information , then the optimal resource scheduling scheme was arrived. Finally, the method of how to use the model to generate the best scheduling plans is given by a specific example.

Abstract: This paper introduces a kind of screening machinery that applied to mineral grading.It needs to simplify its structure for expedient simulation and build the three-dimensional solid model of the screen frame in the SolidEdge circumstance, and then be imported into ADAMS software to improve and perfect the model and conduct the analysis and simulation. Ultimately the curves of motion and changes of pressure angle were obtained. The approximate formula of the screen frames acceleration can be obtained to find out the inertial acceleration of the mineral particles by analyzing and simulating its kinematics, which supplys the basis of Stress analysis of mineral particles on the sifter. It provides a theory to optimize screening machinery by analyzing the changes of pressure angle.