• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.4
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• pp.430-435
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• 2017

The effect of the surface profile on CFRP and aluminum metal bonding was studied. A small number of steps were made on the aluminum surface, and the shear stress and elongation were measured using a shear test after bonding with an autoclave method. As the number of surface steps increased, the shear stress and elongation increased. The surface bonding strength increased because of the effect of the mechanical and chemical bonding. When the number of effective stages was exceeded, the shear strength decreased again due to the aspect ratio of the step and the reduction of the penetration effect of the resin into the groove.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.531-534
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• 2000

The objective of this investigation is to find effects of the pulsatile flow on the morphological changes of the endothelial cell(E.C.) in blood vessel. The shear flow experiment system is used to get the morphological changes of the E.C. The shapes of E.C. are simulated by the cosine curves and computer simulation is used to calculate the pressure and shear stress fields on the E.C. The inlet boundary condition is given from the measured velocity data of femoral artery. The endothelial cells reduce their heights in the flow field so as to reduce the pressure and wall shear stress on the surface. As the exposed time increases, the shear stress and pressure on the E.C. are reduced under the pulsatile flow. The shear stresses on the cell surface show the minimum values during the deceleration phase.

• Journal of Environmental Science International
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• v.5 no.1
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• pp.35-41
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• 1996

For studying of coagulation and sedimentation in estuarine clay, we obtained several flow curves with various concentrations of sea water by using Coutte type rotational rheometer. The initial shear stress on high concentration of sea water was observed big, but after this, its value is decreasing with increasing shear rate. The maximum pick of shear stress is decreasing with the decreasing of concentration of sea water The trend is same totally above for viscosity. The sedimentation times with the concentration of sea water vary in $\infty$ ~ 5 minutes. The zeta potential is changed dramatically between 114 and 118 concentration of sea water. That is consistent with the sedimentation graph. From these results, the phenomena of coagulation and sedimentation can be explained with viscoelastic terms on structual formation among particles by the changes of surface potential affected from contacting sea water to dispersed particles.

• Tribology and Lubricants
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• v.16 no.5
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• pp.341-350
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• 2000

The study reported in this paper deals with the development for parametric investigation of the influence of the rheological properties of the lubricant in the thermohydrodynamic (THD) film conditions which occur in slider and journal bearings. A parametric investigation based on a Bingham model with a shear yield stress which best fit the experimental pressure is performed for predicting the thickness of the shear Bone in lubricating films with fixed geometry between the stationary and moving surfaces. The results suggest that the shear yield stress for the lubricating film is proportional to the pressure developed in the film within the range of the investigated cases and the shear zone thickness which is of the same order of magnitude as that obtained by the empirical formula is significantly smaller than the fluid film thickness in the lubrication zone.

• Journal of Power System Engineering
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• v.22 no.6
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• pp.44-50
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• 2018

As a type of bolt with a spherical head, the ball stud is widely used as a part of a ball joint in steering or suspension systems in automobiles. Balls and studs are subjected to heat treatment suitable for each material; in particular, the shear strength of the ball stud must meet the specifications of the production company. This study evaluated the shear strength of joints according to the cooling method of ball studs subject to resistance welding. The shear stress of water cooling was higher than that of air cooling (as-received material). Note, however, th at oil cooling showed lower stress than that of as-received. When judged by standard deviation, mean, and coefficient of variation according to the arithmetic statistics and shape parameter as well as scale parameter, oil cooling is suitable.

• Advances in concrete construction
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• v.13 no.5
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• pp.361-365
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• 2022

The objective of this study is to simulate the two-phase flow in pipes with various two-fluid models and determinate the shear stress. A hyperbolic shear deformation theory is used for modelling of the pipe. Two-fluid models are solved by using the conservative shock capturing method. Energy relations are used for deriving the motion equations. When the initial conditions of problem satisfied the Kelvin Helmholtz instability conditions, the free-pressure two-fluid model could accurately predict discontinuities in the solution field. A numerical solution is applied for computing the shear stress. The two-pressure two-fluid model produces more numerical diffusion compared to the free-pressure two-fluid and single-pressure two-fluid models. Results show that with increasing the two-phase percent, the shear stress is reduced.

• Coupled systems mechanics
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• v.13 no.2
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• pp.133-151
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• 2024

In this paper, an improved theoretical interfacial stress analysis is presented for simply supported composite aluminum- sandwich honeycomb beam strengthened by imperfect FGM plateusing linear elastic theory. The adherend shear deformations have been included in the present theoretical analyses by assuming a linear shear stress through the thickness of the adherends, while all existing solutions neglect this effect. Remarkable effect of shear deformations of adherends has been noted in the results.It is shown that both the sliding and the shear stress at the interface are influenced by the material and geometry parameters of the composite beam. This new solution is intended for applicationto composite beams made of all kinds of materials bonded with a thin plate. Finally, numerical comparisons between the existing solutions and the present new solution enable a clear appreciation of the effects of various parameters.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.09a
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• pp.777-777
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• 2005

• Journal of the Korean Geotechnical Society
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• v.30 no.1
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• pp.17-25
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• 2014

Offshore wind turbine foundations are subjected to wind, current and wave loadings. Hence, both static and cyclic behaviors of foundation's soil are important for the design of offshore wind turbine foundation. Undrained cyclic behaviors of soils depend upon the number of loading cycles, vertical effective stress, cyclic shear strain, relative density, and the combination of cyclic and average shear stresses. In order to evaluate the effect of average and cyclic shear stresses on the undrained cyclic behavior of marine silty sand, cyclic direct simple shear (CDSS) tests are performed with relative density of 85%, vertical effective stress of 200 and 300 kPa, and failure criteria of either 15% double amplitude cyclic shear strain (${\gamma}_{cyc}$) or permanent shear strain (${\gamma}_{p}$). The results are presented in the form of design graphs or contour diagrams. The undrained cyclic behavior of marine silty sand is found to be dependent on cyclic and average shear stresses and/or the combination of both shear stresses. It is found that when significant average shear stress exists the permanent or progressive shear strain is the govering failure criteria instead of cyclic shear strain.

• Tunnel and Underground Space
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• v.26 no.5
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• pp.384-395
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• 2016

Both the roughness measurement tests and the multi-stage shear tests were carried out on the 110 rock joint samples in order to investigate the influences of rock type, joint roughness and normal stress on the shear behaviour of rock joints. Test samples were composed of quartz porphyry, dacite, granite and gneiss, which were classified into three detailed groups according to their JRC values. Roughness parameters of rock joints were analyzed by roughness measurement tests, and shear characteristics were also investigated by multi-stage shear tests. Both peak shear strength and shear stiffness were increased as both joint roughness and normal stress were increased, whereas dilation angles showed lower values at the lower roughness and higher normal stress conditions. Besides, shear characteristics obtained from all tests of four different rock types with different rock strengths showed irrelevant details, therefore the influences of both joint roughness and normal stress on shear behaviors were found to be more considerable than the strength of intact rock. The results obtained from both multi-stage shear tests and direct shear tests were finally compared, where the dilation angles obtained from multi-stage shear tests were found to be valid only for the first normal stress conditions.