• Journal of Digital Convergence
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• v.18 no.10
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• pp.419-428
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• 2020

This study was intended to academically redefine the art of seal engraving of the Joseon Dynasty through seal analysis related to Kim Jeong-hui and to widely promote its excellence. Previous studies on seals were examined, and comparative studies were conducted focusing on the seals engraved by Kim Jeong-hui and the related seals. The importance of the real seal study, not the stamp, was confirmed. If there was a byeongwan on the side of the seal, it was possible to understand that Kim Jeong-hui directly carved the seal. Also, it was possible to confirm the stone quality of the seal, the method of writing, the method of layout, and the method of holding graver. The imitation seal engraved with a tool rather than hand made it easy to grasp the uncertain production intent. All were analyzed by actual tensile, so it was a possible study result. The results of this study will serve as an indicator to judge the authenticity of the seal when evaluating an ancient painting in the future.

• Journal of the Korean Geotechnical Society
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• v.16 no.5
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• pp.19-25
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• 2000

배수성과 인장강성을 가지는 복합 보강재를 사용하여 보강한 포화점성토의 거동에 선행하중이 미치는 영향을 조사하기위하여 평면변형을 시험을 수행하였다. 보강하지 않은 공시체와 보강한 공시체에 대하여 이방압밀(K=0.3, σ3'=50kPa)을 실시하고 비배수 및 배수전단시험을 일정변형율 속도를 실시하였다. 선행하중을 가한 시험의 경우는 이방압밀후 소정의 선행하중을 가하여 크리이프, 제하, 에이징 후에 비배수 전단시험을 실시하였다. 시험결과 분석한 결과 포화전성성토와 같이 연약한 토질이라도 다짐을 잘하고 보강토의 큰 배수압툭강도를 이용하여 큰 배수압축강도를 이용하여 큰 선행하중을 가하여 과압밀 상태로 함으로써 비배수 전단시에 큰 초기강성을 가지는 것을 알수 있었다. 즉, 점성토의 보강토의 경우 보강에 의한 배수강도의 증가는 큰 선행하중을 가하기 위하여 사용하는 것이 가장 효율적인 것으로 판단된다.

• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.246-253
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• 2003

Although concrete members are not normally designed to resist direct tension, the knowledge of tensile strength is of value in estimating the cracking load. In general, there are three types of test method for tensile strength ; direct tension test, flexural tension test, and splitting tension test. Though direct tensile strength represents the real tensile strength of concrete, direct tension tests are seldom carried out, mainly because it is very difficult to applicate a pure tension force. The purpose of this paper is to investigate the test methods, effect of aspect ratio, and the size effect on the direct tensile strength. Direct tension test, using bonded end plates, follows RILEM and U.S.Bureau of Reclamation. And other test methods follow ASTM provisions. Four kinds of aspect ratio and two kinds of size effect are tested. Same variables are tested by direct tension test and splitting tension test for comparison between the two test methods. Test results show that direct tensile strength of concrete is more affected by aspect ratio and size than other kinds of strength.

• Journal of Korean Society of Steel Construction
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• v.17 no.5 s.78
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• pp.561-568
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• 2005

The object of this paper is to determine appropriateness for use of high-strength tensile bar as a tension web member. The gap K-joint of tensile bar types were compared with gap K-joint of square hollow section (SHS) types. For the same width-to-thickness ratio ($2{\gamma}=33.3$ ), tests were performed on four specimens of the SHS type and eight specimens of the tensile bar type. The comparison of capacity with the experimental results showed a capacity of the SHS type joint to be higher than that of the tensile bartype joint for the same brace-to-chord width ratio. Moreover, the capacity of the SHS type joints increased proportionally to the width ratio ${\beta}$), while tensile bar type joints increased as the tension width ratio (${\beta}2$). In failure mode, SHS-type specimens showed local buckling of the compression brace and plastic failure was observed between the tension brace and chord face, and with the tensile bar type specimens there appeared punching shear failure of the chord face at the toe of the connection plate. It is, therefore, concluded that width-to-thickness ratio should be lower than that of the hollow-section type and the relation between tension and compression width ratio should be considered.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.670-677
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• 2016

Laboratory and meta-analyses were done for 9% NI Steel for use in a liquefied natural gas carrier. The meta-analysis is based on a previous study. The laboratory analysis examines the effects of a single pass and multiple passes on the tensile strength through an impulse-response test. The tensile strength increased from pass one to pass three and decreased from pass four to pass ten. The pass and multi-pass welding had a positive effect on the tensile strength. Lastly, the welding and tensile time had a positive effect on the tensile strength.

• Journal of the Korean Geotechnical Society
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• v.24 no.6
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• pp.37-44
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• 2008

At low normal stress levels, tensile strength of sand characteristically varies with either saturation or suction of soil in an up-and-down manner with a peak tensile strength that can occur at any degree of saturation. A theory that accurately predicts tensile strength of wet sand was presented in the previous study. In this study, the results of uniaxial tensile, suction-saturation and direct shear tests obtained from three sands (Esperance sand from Seattle, Washington, clean sand from Perth, Australia, and Ottawa sand) are used to validate the proposed theory. The closed form expression of the proposed theory can predict well the experimental data obtained from these sands in terms of the variation patterns of tensile strength over the entire saturation regimes, the magnitude of the tensile strength, its peak value, and the corresponding degree of saturation when the peak strength occurs.

• Applied Microscopy
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• v.39 no.1
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• pp.49-56
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• 2009

In this study, we investigated tensile properties and ultrastructural changes of straight permed hair using the rheometer and the scanning electron microscopy. First, we compared the morphological characteristic between the virgin hair and the straight permed hair after testing tensile strength. Cuticle cells were heavily lifted off in straight permed hair than in the virgin hair. Cuticle cells were separated by the destruction of intercellular membrane complex and no destruction or damage were found in cytoplasm. In the comparative test for tensile characteristic between the virgin hair and the straight permed hair, tensile distance of the straight permed hair was decreased by 24.5% or 3.05 mm than the virgin hair. The tensile strength was decreased by 34.63% or $5.62\;g/cm^2$ and the maximum stress by 34.59% or 56.12 g. As a result, the tensile property dropped to the lowest level with the straight permed hair than with the bleached hair or the permanent dyed hair of previous studies.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6C
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• pp.377-384
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• 2006

Theoretical and experimental study of the unconfined penetration (UP) test was conducted to suggest a new test method (referred to as IUP, Improved Unconfined Penetration) for determination of the tensile strength of compacted sand-bentonite mixtures. The tensile strength of compacted mixtures can be calculated from limit analysis based on the theory of perfect plasticity. The measurement errors in new test method were reduced by improving the UP device. Preliminary experiment results indicate that the tensile strength increases with increasing the disk size, loading rate and pH level. In addition, the disk diameter with 25.4 mm and the loading rate with 0.5%/min~1%/min are most suitable condition for the IUP test. The reliability of IPU test was verified by through the fact that good agreement between the IUP and conventional split tensile test results is observed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.3
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• pp.275-281
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• 2011

When a flat bar type metal specimen for general tension test is subject to incremental uniaxial tension, a narrow plastic shear band, so called luders band, is generated at some instance. This band typically has an angle to the axis of specimen and many early researches have been done to investigate the condition and angle of this localized deformation phenomenon by many researchers. This study follows the procedure of Thomas(1961) under plane stress boundary condition. $J_2$ plasticity theory, balance of linear momentum, and constitutive equations are used to derive the angle of luders band under plain strain boundary condition. The result was confirmed by other angle based on acoustic tensor theory.

• Magazine of the Korea Concrete Institute
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• v.9 no.5
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• pp.233-244
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• 1997

구조적으로 손상을 입은 구조물들에 대한 보강방법으로 강판, 카본쉬트, 아라미드섬유쉬트 등을 이용한 접착공법이 최근 들어 많이 사용되고 있으며 그 중 가장 널리 Tm이는 방법은 강판접착공법이다. 강판접착공법에 대해서는 많은 연구가 진행되어 오고 있으나, 보의 구조적 거동에 영향을 미치는 다양한 인자들의 영향이나 강성, 파괴양상등에 미치는 영향들에 대해서는 체계적인 평가가 이루어지지 않은 실정이며 특히 강판접착공법에서 파괴에 큰 영향을 미치는 박리하중에 대한 연구는 미흡한 실정이다. 따라서 본 연구에서는 일련의 철근콘크리트보부재를 대상으로 하여 주요실험변수로 선행하중의 크기, 강판의길이, 강판의 두께, 앵커볼트의 간격과 유무, 강판의 층수, 측면보강높이를 실험변수로 하여, 휨인장에 대해 강판잡착공법을 적용하여 포괄적인 실험을 수행하였다. 3등분점하중법의 실험결과를 이용하여 처짐, 인장 및 압축 철근의 변형도, 콘크리트와 강판의 변형도를 분석하였고, 이를 토대로 파괴양상과 파괴하중을 분석하였다.