Papers by Keyword: Experimental Study

Abstract: We will study the effective value of the angle which affect on the bolted joint surface by the experimental research method. It gets the effective angle under different conditions in the experiment by the way of researching the joint surface stiffness which changing during the joint surface area changing in the paper. This results provide valid reference for the mechanical structure design which with the bolted joint surface, so as to achieving the purpose of more efficiency during the mechanical structure design.

Abstract: A copper-water flat plate heat pipe with intersected micro-grooves was developed for cooling electronic devices in this paper. The effects of heat flux, working fluid filling ratio and inclination angles on thermal performance of the flat plate heat pipe was tested and investigated. The laboratory tests show the optimal filling ratio of the heat pipe is about 65%. Excellent thermal performance is also observed in unfavorable titled positions including vertical and anti-gravity orientation at 65%. The smallest overall thermal resistance is obtained in horizontal position and the maximal thermal resistance is observed in vertical position. The influence of inclination angles on thermal performance of the heat pipe in both axial direction and radial direction is also investigated. As the heat pipe is tilted, the ability of temperature leveling in radial direction is enhanced, nevertheless, the capacity of heat transfer in radial direction decreased at the same time.

Abstract: It based the common strength grade of masonry mortar in construction works on two mixing materials that include composite paste and fly ash paste and an admixture. It spent nearly a year's time on the trial distribution, mixing, forming, form removal, maintenance, measuring strength and adjusting the mix ratio. It’s aimed for seeking the optimum mix proportion of masonry mortar through the comparative analysis of strength of Various proportions of masonry mortar, Promotion and application to be in material engineering.

Abstract: Using the mould pattern contrasting experiments the carrying capacities and deformation effects of underground tunnels within soft bed and top or floor strata are studied under high ground pressures in this paper. Through measuring mould strengths and deformation with different stratum and space position the relations of tunneling positions in different strata with carrying capacity and strains are obtained. It is shown that the soft seam tunneling under high ground pressure can bring about higher secondary stresses and have more acting effects than top or floor tunnels. In the same pressure conditions the carrying capacity of having top tunneling above soft tunnel decreases near 30% with that of having floor tunnel. The mutual effects with double horizontal spaces of tunnels decrease 25%. The experiment conclusions are important significance of conducting and applying for reasonable designing underground tunneling engineering.

Abstract: This paper displays the crack load failure pattern and influences on crack load of reinforced ceramists concrete beams in different reinforcement ratio, concrete cover thickness and diameter of rebar through the experimental study of bending anti-cracking property of 8 reinforced ceramists concrete beams, and proposes the method of calculation cracking moment of normal section for ceramists concrete beam.

Abstract: LRB energy dissipation wall is a type of energy dissipation device for building structures. According to the results of an quasi-static test, structure with LRB energy dissipation wall shows a stronger energy dissipation capacity and a better seismic performance than the normal frame-shear wall structure. This paper also introduces the applications technology of LRB energy dissipation wall in High-level framework structure. According to the dynamic property analysis of a three-dimensional finite element model which was built by the finite element analysis software ETABS, LRB energy dissipation wall can effectively prolong the natural vibration period of high-rise frame structure and significantly reduce the maximum acceleration, shearing force and horizontal displacement in different floors to make the variation more smooth which is important the to the energy dissipation and earthquake mitigation.

Abstract: As for the study on the development regularity of slab concrete cracks under the fatigue loads with amplitude of certain values, two groups of reinforced concrete slab bridge specimen were made. The fatigue test was carried out on one group of specimen, and the corresponding static load test was carried out on another group of specimen, the experimental study on the development regularity of concrete cracks at bottom of slab were carried out. The results of the study shown that, under the fatigue loads at a certain amplitude, the development trend of cracks caused by loading at the bottom of slabs changed more under fatigue loads. The reasons caused the changes of development regularity of concrete cracks were analyzed. The experimental results has the vital significance of further research on the development regularity of concrete bridges under the action of fatigue loads.

Abstract: The concrete simple supported beams were strengthened by an innovative device mainly includes oblique screws and linear CFRP tendons. A static experimental study and finite element analysis were conducted to research the flexural capacity and stress changes of CFRP tendons of strengthened beams, and the contrastive analysis was explored between finite element calculation results and test results. The results indicate that the strengthen system can significantly improve the flexural capacity of concrete beams, there is basically a linear relationship between the stress increment of CFRP tendon and the deflection of midspan section, and the finite element calculation value is in agreement with the test results. Based on this, the stress of concrete near holes was analysed using finite element method (FEM), which can provide a reference for practical engineering application.

Abstract: Through indoor simulation test of double-block ballastless track sleeper loose hydrodynamic pressure, this paper study the variation laws of hydrodynamic pressure of different position, different load and frequency variation. The results show: The location of the biggest hydrodynamic pressure is in the middle of the crack and near the not void area. The amplitude and frequency of load have obvious influence on the hydrodynamic pressure. When the load amplitude is more than 30kN or load frequency exceeds 10HZ, the effect on the hydrodynamic pressure is particularly notable.

Abstract: This article puts the automatic CNC grooving machine as the research object, which oriented by the enterprise's actual demands, and designs the product structure. Furthermore, the paper applies UG/NX 3d modeling and motion simulation to the product. Verify the machining accuracy through experimental study, on this basis, carry through commissioning and improvement to grooving machine, thus it is concluded that the design is feasible.