• 한국농공학회지
• /
• 제38권3호
• /
• pp.58-69
• /
• 1996

In recent years, the research and development about the new material proceeds rapidly and actively. In building industry, high strength concrete is of interest as a new material. Since the building structure becomes bigger, higher and more specialized, the demand of material and member with high strength expands greatly. Therefore in this experiment, cement complex with high strength was made using the condensed silica fume, a basic experiment was performed on strength property, and optimum-mixture-state was determined for manufacturing a high-strength concrete. Shear behaviour and fracture property of concrete beams with high strength were evaluated. On the whole, in spite of many researches, it is one of the difficult problems that shear fracture of concrete beams has not yet been clearly understood theoretically, and now the shear-design-standard forms in many countries are a formula based on experiment. In this study, the variable of shear behavior experiment was shear-reinforcement-ratio. By analyzing test results and comparing with computation value by ACI code, the basic data was offered on shear design of reinforced concrete beams with high strength. The effect of epoxy repair was also investigated for the beams with cracks due to flexural and shear loading.

• Geomechanics and Engineering
• /
• 제5권1호
• /
• pp.71-86
• /
• 2013

For rock materials, a transversely isotropic failure criterion established through the extended Lade-Duncan failure criterion incorporating an anisotropic state scalar parameter, which is a joint invariant of deviatoric microstructure fabric tensor and normalized deviatoric stress tensor, is verified with the results of triaxial compressive data on Tournemire shale. For torsional shear mode with $0{\leq}b{\leq}0.75$, rock shear strengths decrease with ${\alpha}$ increasing until the rock shear strength approaches minimum value at ${\alpha}{\approx}40^{\circ}$, and after this point, the rock shear strengths increase as ${\alpha}$ increases further. For the torsional shear mode with b > 0.75, rock shear strengths are almost constant for ${\alpha}{\leq}40^{\circ}$, but it increases with increase in ${\alpha}$ afterwards. The rock shear strength variation against ${\alpha}$ agrees with shear strength changing tendency of heavily OCR natural London Clays tested before. Prediction results show that the transversely isotropic failure criterion proposed in the paper is reasonable.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권7호
• /
• pp.1054-1058
• /
• 2006

The purpose of this study was to use pig blood plasma transglutaminase (TGase) combined with thrombin and fibrinogen as a binder, which was applied to restructured meat, and to investigate its effect on the restructured meat quality. Pig meat was obtained 10 h post mortem from a traditional market was ground using a 10 mm aperture plate. A binder admixture was added (TGase:thrombin:fibrinogen mixed as 0.5:1:20 (v/v/v) to which was added 12% of its volume of 0.25 M calcium chloride) at 0, 5, 10, 15 and 20% of meat weight. Measurements included cooking loss, shrinkage rate, shear value, total plate count, pH value, TBA value, color difference, tension strength and sensory evaluation. The results showed that ground meat containing 20% w/w of binder admixture had higher cooking loss, shrinkage rate and shear value (p<0.05). Addition of different percentages of binder admixture did not affect total plate count, pH value, TBA value, and sensory evaluation of restructured meat (p>0.05). Tension strength was increased with increased level of binder admixture. Addition up to 15% binder admixture to restructured meat showed better scores of sensory texture, flavor and total acceptability (p<0.05).

• 생명과학회지
• /
• 제7권4호
• /
• pp.329-335
• /
• 1997

This study was conducted to investigate the effect of dietary fiber(DF) levels on the meat quality in colored broiler. Colored broiler were fed on containing corn-soy basal diet(DF 5%) and high level(DF 6,7 and 8%) of dietary fiber diets for 7 weeks. Dietary fiber level of diet was make up by adding some alffalfa meal. Colored broiler meats were stored at 3$\circ$ for 24hr after skaughter, and used to analyze physico-chemical properties. Proximate component, pH, shear force value, myofibril fragmentation index, water holding capacity, cooking loss, protein extractability, fatty acid composition, Hunter's L, a value and palatability of cooked meat were not significantly affected by dietary fiber levels, whereas the Hunter's value of meat was significantly affected bty dietary fiber levels for the final period of feeding. Crude protein content, myofibril fragmentation index, water holding capacity, protein extractability and Hunter's b value of breast meat's were higher than thigh meat's, but crude fat content, pH, shear force value, cooking loss, palmitoleic acid, linolenic acid, and Hunter's a value were lower, regardless of dietary fiber level.

• Geomechanics and Engineering
• /
• 제15권1호
• /
• pp.687-694
• /
• 2018

To investigate the crushing behaviour of coarse granular materials, a specifically designed, large-scale simple shear apparatus with eight-staged shearing rings was developed. A series of monotonic simple shear tests were conducted on two kinds of coarse granular materials under different vertical stresses and large shear strains. The evolution of the particle breakage during the compression and simple shearing processes was investigated. The results show that the amount of particle breakage is related to the particle hardness and the state of the stresses. The amount of particle breakage is greater for softer granular materials and increases with increasing vertical stresses. Particle breakage may tend towards a critical value during both the compression and the shearing processes. Particle breakage mainly occurs during the processes of confined compression and contraction.

• Water Engineering Research
• /
• 제1권4호
• /
• pp.259-266
• /
• 2000

Scour hole is formed due to the high shear stress of the jet flow at the outlet of a hydraulic structure and vortex erosion occurs in the scour hole. It is important to determine the amount of vortex erosion occurs in the scour hole. It is important to determine the amount of vortex erosion for the design of bed protection. If the vortex erosion continues and reaches to the hydraulic structure, it causes the deformation of the structure itself. To obtain the amount of the vortex erosion, it is necessary to determine the shear velocity of the line vortex in the scour hole was derived by the theory of energy conservation and found to be related to the upstream overflow velocity. The amount of vortex erosion from the scour hole was obtained using entrainment equation for given value of shear velocity. For a design purpose, if the flow velocity at the end of an apron and the properties of bed material are given, the amount of vortex erosion was obtained.

• Macromolecular Research
• /
• 제9권3호
• /
• pp.164-170
• /
• 2001

Recently in order to describe the complex rheological behavior of polymer melts with long side branches like low density polyethylene, new constitutive equations called the pom-pom equations have been derived by McLeish and Larson on the basis of the reptation dynamics with simplified branch structure taken into account. In this study mathematical stability analysis under short and high frequency wave disturbances has been performed for the simplified differential version of these constitutive equations. It is proved that they are globally Hadamard stable except for the case of maximum constant backbone stretch (λ = q) with arm withdrawal s$\_$c/ neglected, as long as the orientation tensor remains positive definite or the smooth strain history in the now is previously given. However this model is dissipative unstable, since the steady shear How curves exhibit non-monotonic dependence on shear rate. This type of instability corresponds to the nonlinear instability in simple shear flow under finite amplitude disturbances. Additionally in the flow regime of creep shear flow where the applied constant shear stress exceeds the maximum achievable value in the steady now curves, the constitutive equations will possibly violate the positive definiteness of the orientation tensor and thus become Hadamard unstable.

• Structural Engineering and Mechanics
• /
• 제55권4호
• /
• pp.871-884
• /
• 2015

In the present study, separate and combined effects of rotary inertia, shear deformation and material non-homogeneity (MNH) on the values of natural frequencies of the simply supported beam are examined. MNH is characterized considering the parabolic variations of the Young's modulus and density along the thickness direction of the beam, while the value of Poisson's ratio is assumed to remain constant. At first, the equation of the motion including the effects of the rotary inertia, shear deformation and MNH is provided. Then the solutions including frequencies of the first three modes for various combinations of the parameters of the MNH, depth to length ratios, and shear corrections factors are reported. To show the accuracy of the present results, two comparisons are carried out and good agreements are found.

• 한국시뮬레이션학회논문지
• /
• 제6권1호
• /
• pp.53-60
• /
• 1997

Results from a nonequilibrium molecular dynamics (NEMD) simulation are presented for an argon liquid subject to a shear flow. The segmented molecular dynamics method and the subtraction technique used in NEMD program to reduce the thermal fluctuation noise in data are studied with different shear rates. The standard deviation in the shear stress reduced from 0.030 to 0.004 by the segmented molecular dynamics method for 50 repeated segments. On the other hand, the standard deviation of the data remained the same when the subtraction technique was applied, where as the results of shear stress by constant value in a random way.

• 한국환경과학회지
• /
• 제5권1호
• /
• pp.35-41
• /
• 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.