• 한국지구물리탐사학회:학술대회논문집
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• 2007.06a
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• pp.7-23
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• 2007

The shear wave velocity is directly related to the deformation characteristic of soils which is an engineering property represented by the shear modulus. This feature presents an opportunity of advantageous utilization of the shear wave velocity for deformation analysis in geotechnical engineering applications, since the deformation modulus is determined on strong theoretical basis, whereas penetration resistances such as N by SPT or qc by CPT rely on empirical relations. Furthermore, it is an engineering property that can be evaluated by performing the same basic measurement in the laboratory and field, and various problems in geotechnical engineering can be dealt with economically and reliably when the field and laboratory methods are combined effectively. In this article, assessment of nonlinear deformation characteristic of soils based on synergic use of the field and laboratory test results is described, and representative case histories of geotechnical applications of the shear wave velocity are illustrated.

• The Journal of the Acoustical Society of Korea
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• v.23 no.3
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• pp.197-205
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• 2004

This paper represents the results of interpretation on the cause of sign changing of the striation slopes appearing in the range-frequency domain spectrogram of ship-radiated noise measured in a shallow sea. Striation patterns and dispersion characteristics simulated from a numerical model based on mode theory at various seabed conditions show that the sign changing of the striation slopes appearing in measured signal is caused by the shear property of seabed. more specifically by the shear property of the basement lying below the sediment which is estimated about 3±1m thick.

• Journal of the Korean Geotechnical Society
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• v.33 no.4
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• pp.17-24
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• 2017

Shear wave velocity (or shear modulus) of rock filled zone of CFRD is very important factor in the evaluation of performance of CFRD under the load such as earthquake. A shear wave velocity profile can be determined by surface wave method but this profile has been uncertainty caused by spatial variation of material property in rock filled zone. This uncertainty in shear wave velocity profile could be evaluated by the reliability based analysis which uses a coefficient of variation of material property to consider uncertainty caused by spatial variation of material property. In this paper, the possible 600 shear wave velocity profiles in rock filled zone of CFRD were generated using the method based on harmonic wavelet transform and 8 shear wave velocity profiles by HWAW method in the field, and the coefficients of variation of shear wave velocity with depth were evaluated for the rock filled zone of CFRD in Korea.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.189-192
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• 2007

The qualification test of rubber product is consisted of uniaxial tensile, pure shear, biaxial and compression test. Uniaxial test result is used for material property of Finite Element Method. Comparison of uniaxial tensile test and analysis satisfied requirement. A study has qualificated result of QLS analysis model for material property of uniaxial test and shear modulus.

• Transactions of Materials Processing
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• v.12 no.6
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• pp.582-587
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• 2003

This paper is concerned with the mechanical property changes of the milli-size products manufactured by forward extrusion processes with square dies. Experiments are carried out with pure aluminum and pure copper billets. Extrusion ratio and knock-out pad are chosen as the important process parameters affecting the changes of mechanical properties such as shear strength and hardness. Shear strength tests with the extruded milli-size pin have shown the strong relation between victors hardness and shear strength in the neck of a stepped pin. As the extrusion ratio increases, the hardness on both the surface and the center line of a pin also increase. It is also noted that the hardness on the surface is a little higher than that on the center. The existence of knock-out pad in extrusion die causes the hardness in the neck of a extruded pin to increase. Finally, the approximated linear relations between shear strength and hardness of a pin are suggested.

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.3
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• pp.58-69
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• 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.

• Steel and Composite Structures
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• v.38 no.3
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• pp.271-280
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• 2021

In this study, the fatigue property of U rib-to-crossbeam connections in orthotropic steel bridge (OSB) crossbeams under heavy traffic vehicle load was investigated considering the effects of in-plane shear stress. The applicability of an improved structural stress (ISS) method was validated for the fatigue behavior analysis of nonwelded arc-shaped cutout regions in multiaxial stress states. Various types of fatigue testing specimens were compared for investigating the equivalent structural stress, fatigue crack initiation positions, and failure modes with the unified standards. Furthermore, the implications of OSB crossbeams and specified loading cases are discussed with respect to the improved method. The ISS method is proven to be applicable for analyzing the fatigue property of nonwelded arc-shaped cutout regions in OSB crossbeams. The used method is essential for gaining a reliable prediction of the most likely failure modes under a specific heavy traffic vehicle load. The evaluated results using the used method are proven to be accurate with a slighter standard deviation. We obtained the trend of equivalent structural stress in arc-shaped cutout regions and validated the crack initiation positions and propagation directions by comparing them with the fatigue testing results. The implications of crossbeam spans on fatigue property are less significant than the effects of crossbeams.

• Steel and Composite Structures
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• v.26 no.2
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• pp.183-196
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• 2018

The traditional prestressed concrete composite box-girders with corrugated steel webs have several drawbacks such as large deflection and potential local buckling. In this study, two methods were investigated to optimize and improve the prestressed concrete composite box-girders with corrugated steel webs. The first method was to replace the concrete bottom slab with a steel plate and the second method was to support the concrete bottom slab on the steel flanges. The behavior of the prestressed concrete composite box-girders with corrugated steel webs with either method was studied by experiments on three specimens. The test results showed that behavior of the optimized and upgraded prestressed concrete composite box-girders with corrugated steel webs, including ultimate bearing capacity, flexural stiffness, and crack resistance, is greatly improved. In addition, the influence of different shear connectors, including perfobond leisten (PBL) and stud shear connectors, on the behavior of prestressed concrete composite box-girders with corrugated steel webs was studied. The results showed that PBL shear connectors can greatly improve the ultimate bearing capacity, flexural stiffness and crack resistance property of the prestressed concrete composite box-girders with corrugated steel webs. However, for the efficiency of prestressing introduced into the girder, the PBL shear connectors do not perform as well as the stud shear connectors.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.1 s.24
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• pp.9-14
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• 2006

Analysis has been made of the anti-corrosive property of organic coating under the shear stress of the flow by means of AC impedance method. Marine anti-corrosive painted panels were placed in the water channel with varying flow rate, thereby experiencing varying flow shear stress on the surfaces. The velocities of the salt water were ranged from 1.48 to 5.2 m/s and the coating thickness of from $70{\mu}m\;to\;140{\mu}m$. For all coating thicknesses investigated, the poorer anti-corrosive property and the lower adhesion strength have been found for the higher shear stress. It has been found that the shear stress accelerates the aging of organic marine coatings.

• Journal of Technologic Dentistry
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• v.35 no.4
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• pp.359-364
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• 2013

Purpose: This study was to observe characteristic of metal oxidation and bonding strength according to composition of Ni-Cr alloy for porcelain fused to metal crown. The three kinds of Ni-Cr alloy with different composition ratio of parent metal were observed general properties and chemical properties of each alloy surface and measured the shear bonding strength between ceramic and each alloys. The aim of study was to suggest the material for design of parent metal's composition ratio to development of alloy for porcelain fused to metal crown. Methods: The three kinds of alloy as test specimen was Ni(59wt%)-Cr(24wt%), Ni(67wt.%)-Cr(16wt.%) alloy and Ni(71wt%)-Cr(12wt%)alloy. The oxide on surface was observed by EDX. And the shear test was performed by MTS. Results: The surface property and oxide characteristic analysis of oxide layer, weight percentage of Element O within $Ni_{59}Cr_{24}$ alloy measured 23.03wt%, $Ni_{67}Cr_{16}$ alloy measured 21.13wt% and $Ni_{71}Cr_{12}$ alloy was measured 48.55wt%. And the maximum shear bonding strength was measured 58.02Mpa between $Ni_{59}Cr_{24}$ alloy and vintage halo(H2 group). Conclusion: The surface property and oxide characteristic three kind of Ni-Cr alloy was similar. and shear bonding strength showed the highest bonding strength in H2 specimens.