• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.89-92
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• 1995

For the development of lilght weight cement concrete with high durability, this study used perlite and paper sludge ash by the light weight material, and polypropylene fiber by the reinforcment, and poly-acrylic ester emulsion by the matrix improvement. According to the increasing mixture ratio of fiber and use of polymer, the light weight polypropylene fiber reinforced polymer cement ratio of fiber and use of polymer, the light weight polypropylene fiber reinforced polymer cement concrete were showed high resistance for frost damage.

• 한국농공학회논문집
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• 제59권6호
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• pp.19-27
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• 2017

This study investigated to predict the compressive strength of unsaturated polyester resin based polymer concrete using the maturity method. The test results show that the development of the compressive strength increased exponentially until an age of 24 hours. After 24 hours, the development of the compressive strength just increased gradually. This test result shows that the strength of unsaturated polyester resin based polymer concrete was developed mainly at the early age. Estimated datum temperature of unsaturated polyester resin based polymer concrete was $-20.67^{\circ}C$ which was much lower than of datum temperature ($-10^{\circ}C$) of Portland cement concrete. Also, this study result shows that the existing maturity index associated with Portland cement concrete was not applicable for polymer concrete because curing time of Portland cement concrete is different clearly with curing time of polymer concrete. The cause of different curing time was that there were different curing mechanisms between Portland cement concrete and polymer concrete. In order to best apply the experimental data to a model, CurveExpert Professional, the commercial software, was used to determine the predictive model regarding the compressive strength of unsaturated polyester resin based polymer concrete. As a result, Gompertz Relation or Weibull Model was an appropriate model as a predictive model. The proposed model can be used to predict the compressive strength, especially, it is more useful when the maturity is in the range between $40^{\circ}C{\cdot}h^{0.4}$ and $900^{\circ}C{\cdot}h^{0.4}$.

• 한국농공학회논문집
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• 제60권1호
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• pp.101-110
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• 2018

This study experimentally investigated the compressive and flexyral strength development characteristics of polymer concrete using four different type polymeric resins such as unsaturated polyester, vinyl ester, epoxy, and PMMA (polymethyl methacrylate) as binders. The test results show that the average compressive strength of those four different polymer concretes was 88.70 MPa, the average flexural strength was 20.30 MPa. Those test results show that compressive and flexural strengths of polymer concrete were much stronger than compressive and flexural strengths of ordinary Portland cement concrete. In addition, the relative gains of the compressive strength development at the age of 24 hrs compared to the age of 168 hrs were 68.6~88.3 %. Also, the relative gains of the flexural strength development at the age of 24 hrs compared to the age of 168 hrs were 73.8~93.4 %. These test results show that compressive and flexural strengths of each polymer concrete tested in this study were developed at the early age. Moreover, the prediction equations of compressive and flexural strength developments regarding the age were determined. The determined prediction equations could be applied to forecast the compressive and flexural strength developments of polymer concrete investigated in this study because those prediction equations have the high coefficients of correlation. Last, the relations between the compressive strength and the flexural strength of polymer concrete were determined and the flexural/compressive strength ratios were from 1/4 to 1/5. These results show that polymer concretes investigated in this study were appropriate as a flexural member of a concrete structure because the flexural/compressive strength ratios of polymer concrete were much higher than the flexural/compressive strength ratios of Portland cement concrete.

• 한국농공학회논문집
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• 제52권6호
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• pp.101-110
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• 2010

This study was performed to evaluate the void ratio and strength of porous polymer concrete used coarse aggregates and unsaturated polyester resin to find optimum mix design of porous polymer concrete for planting block. Also, this study was performed to evaluate the planting properties of herbaceous plant and cool-season grass in porous polymer blocks based on the experimental results of porous polymer concrete to develop environmentally friendly planting blocks. Tests for the void ratio and compressive strength of porous polymer concrete were performed at the curing age 7 days. Also, kinds of plants such as Tall fescue, Perennial ryegrass, Lespedeza and Alfalfa for planting were applied to porous polymer blocks. Within 6 weeks after seed, initial germination ratio, cover view and growth length for planting blocks were estimated by various methods.

• 콘크리트학회논문집
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• 제14권3호
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• pp.402-408
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• 2002

본 연구에서는 SBR 라텍스 및 재유화형 EVA 분말수지를 혼입한 투수성 폴리머 시멘트 콘크리트를 제조하여 투수성 폴리머 시멘트 콘크리트의 공극률, 투수계수, 강도 및 동결융해 저항성에 미치는 폴리머-시멘트비의 영향을 구명하였다. 그 결과, 투수성 폴리머 시멘트 콘크리트의 공극률, 연속공극률 및 투수계수는 폴리머-시멘트비의 증가에 따라 감소하는 경향을 보였으며, 압축, 인장 및 휨강도는 폴리머-시멘트비의 증가에 따라 증가하였다. 또한 투수성 폴리머 시멘트 콘크리트의 동결융해 저항성 역시 폴리머의 혼입에 따라 증진되었다. 이와 같은 효과는 폴리머의 혼입에 의해 시멘트 수화물과 골재간의 접착성이 개선되기 때문이라 판단된다.

• 한국농공학회논문집
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• 제58권3호
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• pp.21-27
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• 2016

This study was performed to evaluate engineering properties of carbon and glass fiber reinforced recycled polymer concrete. Fiber reinforced recycled polymer concrete were used recycled aggregate as coarse aggregate, natural aggregate as fine aggregate, $CaCO_3$ as filler, unsaturated polyester resin as binder, and carbon and glass fiber as fibers. The compressive and flexural strength of carbon fiber reinforced recycled polymer concrete were in the range of 68~81.5 MPa and 19.1~21.5 MPa at the curing 7days. Also, the compressive and flexural strength of glass fiber reinforced recycled polymer concrete were in the range of 69.4~85.1 MPa and 19~20.1 MPa at the curing 7days. Abrasion ratio of carbon and glass fiber reinforced recycled polymer concrete were decreased 21.6 % and 11.6 % by fiber content 0.9 %, respectively. After impact resistance test, drop numbers of initial and final fracture were increased with increase of fiber contents. Accordingly, carbon fiber and glass fiber reinforced recycled polymer concrete will greatly improve the hydraulic structures, underground utilities and agricultural structures.

• 콘크리트학회지
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• 제9권4호
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• pp.197-205
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• 1997

폴리머 콘크리트를 오버레이 콘크리트로서 기존 시멘트 콘크리트 위에 타설할 경우 폴리머 콘크리트의 경화수축으로 말미암아 전단응력, 수직응력 및 축응력이 발생되며 이러한 응력은 폴리머 콘크리트와 기존 시멘트 콘크리트 사이의 접착성능에 영향을 미쳐 결국 역학적 성질 및 내구성이 저하될 수 있다. 오버레이 콘크리트의 수축응력은 본 실험에서 실시한 구속된 오버레이 콘크리트의 구속해제에 의한 수축변형량과 탄성계수로서 구할 수 있다. 본 연구에서는 폴리머 종류, 오버레이 콘크리트 두께, 양생시간과 온도에 따른 폴리머 콘크리트 및 폴리머 시멘트 콘크리트의 수축에 의한 축응력을 측정하여 폴리머 콘크리트를 각종 교량등의 오버레이 콘크리트로 사용하멩 있어서 기초적 자료를 제공하고자 하였다. 연구결과, 폴리머 콘크리트의 경화수축응력은 폴리머의 종류, 양생온도, 재령 및 두께에 의해 영향을 크게 받는 것으로 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.117-122
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• 2001

Recently, epoxy-coated re-bar used to the structure partly and put to practical use step, but not economical and appeared to the defect of deterioration of long term bond strength between concrete. The method for complement the defect of epoxy coated re-bar, study of polymer cement slurry coated re-bar started and basic properties appeared to excellent, but study of bond properties embedded in concrete specimens insufficient until now. This study attempts to examination of using possibility for bond strength of polymer cement slurry coated re-bar between concrete specimens compare to ACI Code and KS Code through pull-out test of 15cm$\times$15cm$\times$15cm specimens with polymer cement slurry coated re-bar as polymer cement ratio 50%, 100%, 150%, coating thickness 250${\mu}{\textrm}{m}$, 440${\mu}{\textrm}{m}$ and curing age. In the results of this study, the bond strength of polymer cement slurry coated re-bar compare to plain re-bar, epoxy coated re-bar decreased St/BA-modified polymer cement slurry coated re-bar, but bond strength of PA-modified polymer cement slurry coated re-bar appeared to excellent results. The bond properties of polymer cement slurry coated re-bar between concrete will be obtain more precise results according to compressive strength change of concrete and re-bar diameter size.

• Computers and Concrete
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• 제24권5호
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• pp.413-422
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• 2019

In this study, 3D Meso-scale finite-element model is presented to study the mechanical behavior of steel microfiber-reinforced polymer concrete considering the random distribution of fibers in the matrix. The composite comprises two separate parts which are the polymer composite and steel microfibers. The polymer composite is assumed to be homogeneous, which its mechanical properties are measured by performing experimental tests. The steel microfiber-polymer bonding is simulated with the Cohesive Zone Model (CZM) to offer more-realistic assumptions. The CZM parameters are obtained by calibrating the numerical model using the results of the experimental pullout tests on an individual microfiber. The accuracy of the results is validated by comparing the obtained results with the corresponding values attained from testing the steel microfiber-reinforced polymer concrete incorporating 0, 1 and 2% by volume of microfibers, which indicates the excellent accuracy of the current proposed model. The results show that the microfiber aspect ratio has a considerable effect on the mechanical properties of the reinforced polymer concrete. Applying microfibers with a higher aspect ratio improves the mechanical properties of the composite considerably especially when the first crack appears in the polymer concrete specimens.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.357-362
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• 1997

The purpose of this study is to evaluate the adhesion of concrete pipe lining using polymer mortar. The polymer mortars with various mix proportions are prepared, and tested for flexural and compressive strengths, adhesion in tension, and the aspects of lining surface and workability are evaluated. Form the test results, it is apparent that the appropriate polymer mortars of lining to concrete pipe can be produced. The flexural and compressive strengths of polymer mortar for lining are affected by type of resin, and aggregates content, and water content at the surface of concrete pipe is important factor for improvement in adhesion of polymer mortar. It is obvious that the economical polymer mortars having an excellent cost performance ration can be produced through this study.