Applied Mechanics and Materials Vols. 170-173

Abstract: Emulsion explosive have well frost resistance, it can be stably detonated at -300C. But there are many misfires occurred in blasting construction of shaft frozen zone. After analysis, the causes was water in the hole frozen and it’s volume increased, so explosive cartridge was pressed, it’s density enlarged, and misfire created when it’s density exceed critical density of stable detonation. Based on analysis, plastic tube casing charge adopted for construction, and prevent misfire effectively.

Abstract: With the improved triaxial equipment, the tests of research of the relationships between matrix suction and water content are performed And based on the test data, the curves between matrix suction and water contents under different confining pressures are drawn and the change rule between them are analyzed. And then the function between them is simulated out. Through the soil-water characteristic curve, the permeability coefficient of unsaturated soil can be calculated and the shear strength of unsaturated soil can be predicted. These results are important to research the engineering properties of unsaturated soil.

Abstract: The dynamic compaction parameters and measures for tailings foundation are proposed based on actual engineering field testing result.Results of field loading test,standard penetration test and pore water pressure test show that when tailings foundation is reinforced by dynamic compaction method,the bearing capacity value is greater than 130kpa.These provide a reference to application research of dynamic compaction in the tailings foundation.

Abstract: For understanding the dynamic characteristics and improving the stability of the main frame of the horizontal type high-pressure grouting machine, the finite element analysis software ANSYS is applied to the modal analysis of the main frame based on the theory of finite element and vibration mechanics, and the first six natural frequencies and the corresponding vibration modes of the main frame are obtained. The influence of each vibration mode to the working condition of the main frame is analyzed, and provides some reference to improve and enhance the design of the main frame of horizontal type high-pressure grouting machine.

Abstract: Vibration induced by blasting is one of the most hazardous events in the mining industry and may cause structural damage in country areas. Therefore, mitigating the possible hazard and predicting the vibration velocity is important. In this paper, an attempt has been made to predict the peak particle velocity using artificial neural network (ANN) by taking into consideration of maximum explosive charge used per delay and distance between blast face to monitoring point. To achieve the classic framework of this approach, the prediction results by artificial neural network were compared with measured values by coefficient of determination (CoD) and sum of squares due to error (SSE).

Abstract: Method of jet grouting has become one of the ground improvement technologies used to address seepage concerns and to provide strength improvement of soils. The soilcrete columns can be also used to form seepage vertical cut-off walls from a series of continuous and interconnected vertical columns in deep pit. If the native soil is not completely mixed with slurry, the resulting columns will have soil inclusions which can increase the permeability of the column or fail barrier to water flow. Specifications of soilcrete columns that are achieved from the jet grouting procedures from the diameter and strength aspect depend on jet grouting parameters such as grout pressure, lifting speed, number and diameter of nozzles and c/w ratio and specifications of local soil. Different soil must use different jet grouting parameters.

Abstract: Abstract. This paper discusses a lift slab building with concrete filled steel tube columns. Lift slab construction as a methodology has advanced on improvements in traditional lift slab construction technology. When concrete filled steel tube columns are used, the strength of the concrete in the tube is obviously enhanced by the hoop action derived from the steel tube. The section of the concrete filled steel tube column is smaller than the section of the reinforced concrete column, thus realizing cost savings in material and labor. Also, because the steel tube hasn’t been filled with concrete when it is assembled, the steel tube is much lighter than the traditional reinforced concrete column. Thus, the assembly of steel tube columns without concrete is easier and crane-lifting requirements are less. This paper describes the construction of a building utilizing current LSCSTC – Lift Slab Construction with Concrete filled Steel Tube Column technology.

Abstract: The strength and stiffness characteristics are important parameters in the design of metal structure of gantry crane. In this paper, the modeling of a gantry crane before and after reconstruction was performed by using Finite Element Method, and the strength and static stiffness of the gantry crane were analyzed. The results show that the insufficient stiffness of the reconstructed gantry crane in the shaking direction causes its laterodeviation. A strengthened method was determined after comparison of four reinforcement measures. The present results can provide an importantly theoretical basis for the reconstruction or strengthening of gantry cranes.

Abstract: The large-scale steel dome construction method is studied in the paper. Combined with Shandong province museum of steel construction dome, the piecewise processing methods are determined. According to the type of weight component chose lifting equipment types and model, aiming at the actual situation of construction formulated the steel structure installation overall process, the stress of the bed-jig to install a performance is calculated, and the steel frame column installation method is studied. The engineering experience and research content in the paper can provide a reference for the similar engineering.

Abstract: According to processing characteristics of getting rectangular holes after forming of the cylindrical part with prefabricate-holes, the optimum blank shape of the cylindrical part is necessary to improve product quality and reduce production cost. Theory analysis and numerical simulations combined with inverse finite element method and forward finite element method by using ETA/ DYANFORM were employed to investigate the influence on blank shape by the holes, modify the reverse blank shape and optimize the deep drawing by forward simulation,and finally obtain the forming law of the cylindrical part with prefabricate-holes.