• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.181-182
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• 2021

Selecting a proper tile cement for ceramic tile is important to secure tile construction quality. But there is some ambiguity in standards about evaluating adhesion test such as using KS L 1593 in Lab test but using KS L 1592 in site. So, this study aims to how to select proper tile cement for securing adhesion strength in site considering both tensile and shear adhesion strength of cement for ceramic tile. Also, when doing tensile adhesion test in site, there may be adhesion drop because of cutting tile with grinder. As a result, drop of adhesion strength is about 9% ans quality manager consider these factor and should select proper tile cement.

• 대한건축학회논문집:구조계
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• 제35권11호
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• pp.147-154
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• 2019

The purpose of this study is to evaluate the effect of admixtures as blast-furnace slag(BF) and fly ash(FA) on tensile and adhesive properties of polymer cement mortar(PCM) with EVA emulsion. The test specimens are prepared with five polymer-cement ratio(P/C) and five admixture contents, and tested for tensile strength and adhesion in tension. From the test results, the tensile strength and adhesion in tension could be improved by an appropriate combination of P/C and admixture contents. In particular, the maximum of tensile strength of PCM with P/C 10% and BF content of 10% is 4.70MPa which is about 1.55 times higher than that of plain mortar, and about 1.22 times that of PCM that does not contain any mixture. The ratio of adhesion in tension to tensile strength of PCM with admixtures averaged 55.8%. It is also apparent that admixture contents of 5% or 10% could be proposed for improvement of tensile strength and adhesion in tension of PCM.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.222-225
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• 2006

Pull-off test is widely used to evaluate bond performance between concrete and FRP composite. However, reliability of experiment result declines due to many difference between test methods of each national standards. This study analyzed problems of various existing test methods for pull-off test and suggested standardized test method. In addition, since tensile strength of concrete is smaller than bond strength of epoxy resin, maximum bond strength of epoxy resin shall be limited within tensile strength of concrete. Alternative testing method, therefore, which decrease FRP adhesion areas than concrete adhesion areas is suggested to widen test range of bond strength in pull-off test. In the experimental results, bond performance can be estimated up to two times of tensile strength of concrete by reducing FRP adhesion areas by 1/3.

• Journal of the Korean Wood Science and Technology
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• 제25권3호
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• pp.16-23
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• 1997

This study was carried out to discuss feasibility of high density polyethylene(HDPE) as a new substitute for the conventional adhesives in plywood manufacture. Plywood was composed of radiata pine(Pinus radiata) and Malas(Homallium feotidium) veneers and bonded by HDPE. Adhesion characteristics and anatomical scanning has been examined through tensile-shear strength test and scanning electron microscopy(SEM). The results are as follows; 1. Optimum loading quantity was 15g/$(30.3{\times}30.3)cm^2$, and tensile-shear strength increased with the increase of loading quantity. 2. Even at the hot pressing time of 1 minute, tensile-shear strength met the value of KS(over the 7.5kgf/$cm^2$), and tensile-shear strength increased with the increase of hot pressing time. 3. Plywood composed of veneer at moisture content of 19.6% showed similar tensile-shear strength to that at air conditioned moisture content of 11.4%. 4. Under the same condition of hot pressing time, tensile-shear strength of plywood bonded by HDPE met the KS value of boil and wet test and proved the same group as phenol formaldehyde adhesive. 5. HDPE films showed mechanical adhesion through penetration into the lathe check and ray of veneer.

• 한국환경과학회지
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• 제23권11호
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• pp.1909-1918
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• 2014

In this experiment no solvent based polyurethane(PU) adhesives were prepared with the polyol, isocyanate, dioctyl phthalate(DOP), 2-hydroxyethylacrylate(2-HEA) and other acrylate monomers. The softenening point of the PU adhesives measured by Ring & Ball method were examined in the present study. And adhesion strength and mechanical properties such as tensile strength and 100% modulus of the PU adhesives were evaluated by Universal Test Machine. The experimental results showed that increase of both DPE-41, benzoylperoxide(BPO) and toluene diisocyanate(TDI) increased softenening point, adhesion strength, tensile strength and 100% modulus. However as DOP content increased sofenening point, adhesion strength decreased and tensile strength, 100% modulus also decreased.

• 접착 및 계면
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• 제5권2호
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• pp.22-36
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• 2004

Several in-situ testing methods of adhesively bonded joints under static short-time tensile loading are critically analyzed in terms of experimental procedure and data evaluation. Due to its rather homogeneous stress state across the glue line, the tensile-shear test with thick single-lap specimens, according to ISO 11003-2, has become the most important test process for the determination of realistic materials parameters. This basic method, which was improved in both, the experimental part by stepped adherends and easily attachable extensometers and the evaluation procedure by numeric substrate deformation correction and test simulation based on the finite element method (FEM), is therefore demonstrated by application to several kinds of adhesives and metallic adherends. Multi-axial load decreases the strength of a joint. This effect, which is illustrated by an experimental comparison, impedes the derivation of realistic mechanical characteristics from measured force-displacement curves. It is shown by numeric modeling that tensile-shear tests with thin plate substrates according to ISO 4587, which are widely used for quick industrial quality assurance, reveal an inhomogeneous stress state, especially because of relatively large adherend deformation. Complete experimental determination of the elastic properties of bonded joints requires independent measurement of at least two characteristics. As the thick-adherend tensile-shear test directly yields the shear modulus, the tensile butt-joint test according to ISO 6922 represents the most obvious complement of the test programme. Thus, validity of analytical correction formulae proposed in literature for the derivation of realistic materials characteristics is verified by numeric simulation. Moreover, the influence of the substrate deformation is examined and a FEM correction method introduced.

• 한국건축시공학회지
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• 제19권6호
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• pp.485-494
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• 2019

본 연구는 고로슬래그 미분말 및 플라이애쉬를 혼입한 SAE 에멀젼 기반 폴리머 시멘트 모르타르의 휨과 인장특성에 대하여 실험하여 혼화재의 혼입효과를 평가하고자 하였다. PCM은 폴리머 시멘트비와 혼화재의 혼입율을 변화시켜 시험편을 제작하였으며, 휨강도, 휨접착강도, 인장강도 및 인장접착강도 시험을 실시하였다. 연구결과, 혼화재의 혼입에 따른 휨강도 및 휨접착강도 개선은 거의 발현되지 않았으나, 인장강도 및 인장접착강도에서는 혼화재의 혼입에 따른 강도개선 효과를 얻을 수 있었다. 특히 PCM의 인장 접착강도는 P/C 20%, 고로슬래그 미분말 혼입율 10%에서 최대 3.35MPa로 보통시멘트 모르타르의 약 2.36배, 혼화재를 혼입하지 않은 PCM의 약 1.32배의 높은 강도를 나타냈으며 인장접착강도/인장강도비는 평균 48.7%를 나타냈다. 본 연구를 통하여 PCM의 인장 및 인장접착강도 개선을 위해서는 혼화재 혼입율 5% 또는 10%를 제안할 수 있었다.

• Journal of Welding and Joining
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• 제11권4호
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• pp.91-102
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• 1993

The plasma sprayed $Cr_3C_2$-NiCr coatings are widely used as wear-resistant and corrosion-resistant materials. The mechanical and wear properties of the plasma sprayed $Cr_3C_2$-NiCr coating on steel plate were examined in this study. The pore in the coatings could be classified into two types, the one is the intrinsic pore originated from the spraying powder, the other is the extrinsic pore formed during spraying. During the tensile adhesion test, the fracture occured at the interface of top coating and bond coating. It is though that the compressive residual stress increases with the increase of the top coating thickness. From the wear test, it was found that the wear rate increased with the increase of the sliding velocity regardless of the temperature. It is thought that the fracture toughness reduces with the increase of the sliding velocity at $30^{\circ}C$ and that the adhesion amount increases with the increase of the sliding velocity at $400^{\circ}C$ It is concluded that the wear mechanism at $30^{\circ}C$ is the fracture and pull-out of the carbide particles due to the fatigue on sliding surface, while the wear mechanism at $400^{\circ}C$ is the adhesion of the smeared layer formed during wear process.

• 한국건축시공학회지
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• 제19권1호
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• pp.47-57
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• 2019

폴리머 종류에 상관없이 폴리머 시멘트비의 증가에 따라 접착성능은 크게 개선되었으며, A타입 인장접착강도는 1.90배, B 타입 인장(접착)강도는 2.17배, 휨(접착)강도는 1.83배 보통 시멘트 모르타르 보다 높게 나타났으며, 보통 시멘트 모르타르의 B 타입 인장(접착)강도에 대한 인장강도비와 휨(접착)강도에 대한 휨강도비인 상대강도비가 각각 46.9%, 72.6%를 나타냈으며, 폴리머 시멘트 모르타르의 경우에는 각각 50.1%~101.7%, 73.8%~132.9% 범위를 나타내, 폴리머 시멘트 모르타르가 높은 강도회복율을 보였다. 폴리머 종류에 따라서는 EVA를 사용하고, 폴리머 시멘트비로서는 접착성능과 경제성을 고려하면, P/C 10%~15% 범위를 제안할 수 있다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.597-600
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• 2003

The development and maintenance of a sound bond are an essential requirements of concrete repair and replacement. The bond property of a bonded overlay to its substrate concrete during the lifetime is one of the most important performance requirements which should be quantified. A standard or a verified bond strength measurement method is required at field for screening, selecting materials and quality control for overlay or repair materials. This study compares the nipple pipe direct tensile test, flexural adhesion test, and core pull-off test with their test results. Substantial differences in the failure stresses of three test methods were attributed to their different geometries and loading conditions. From these comparison and investigation, core pull-off test was relatively good because the coefficient of variation values were about 2%. It would be suitable for use in-situ because of its simplicity and accuracy.