• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.830-834
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• 2008

Resilient materials are generally used for the floating floors to reduce the floor impact sound. Dynamic stiffness of resilient material, which has the most to do with the floor impact sound reduction. The resilient materials available in Korea include EPS (Styrofoam), recycled urethane types, EVA (Ethylene Vinylacetate) foam rubber, foam PE (Polyethylene), glass fiber & rock wool, recycled tire, foam polypropylene, compressed polyester, and other synthetic materials. In this study, we tested floor impact sound reduction characteristic to a lot of kinds of resilient material. The result of test showed that the amount of the Light-weight impact sound reduction appeared by being influenced from this dynamic stiffness of resilient material. As the decreasing dynamic stiffness of resilient material, the impact sound reduction amount is increased, especially in the low frequency domain.

• Advances in concrete construction
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• 제9권5호
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• pp.479-489
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• 2020

Studies have proved that the mechanical properties of concrete, suddenly is dropped off with employing waste materials as replacements. The effectiveness of fibre addition on the structural stability of concrete has been indicated in recent investigations. There are different waste aggregates and fibres as plastic, rubber tire, coconut, and other natural wastes, which have been evaluated throughout the last decades. The fibres incorporation has a substantial effect on the properties of concrete mix subjected to different loading scenarios. This paper has reviewed different types of wastes and the effect of typical fibres including Poly Ethylene Terephthalate (PET), rubber tire, and waste glass. Furthermore, waste plastic and waste rubber has been especially studied in this review. Although concretes containing PET fibre revealed a reduction in compressive strength at low fibre fractions, using PET is resulted to micro-cracking decrement and increasing flexibility and flexural strength. Finally, according to the reviews, the conventional waste fibres are well-suited to mitigated time-induced damages of concrete and waste fibres and aggregates could be a reliable replacement for concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.167-168
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• 2020

In order to expand the material recycling of waste plastics made of composite materials, it is necessary to develop the use of material recycling products and to secure their quality stability. In this paper, as a basic study to secure the stability of the quality of household waste plastic material recycling products, the quality characteristics of recycled materials according to the production period were compared and reviewed. In addition, the average tensile strength of the recycled products by production period for 4 months was 12.33 MPa, and the average density was 1.35 g/m3.

• 한국지반환경공학회 논문집
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• 제13권2호
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• pp.67-73
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• 2012

폐아스콘은 순재료와 첨가제를 섞어 분쇄와 가열을 통하여 재활용될 수 있다. 본 연구에서는 고품질재생아스팔트(SRP)의 질을 향상시키기 위하여 Sasol 왁스와 폴리올레핀 탄성체를 이용하였다. 첨가제로써 중간층 및 표층용은 PG 70-22를 목표로 아스팔트량의 1.5%를 사용하였고, 중교통 표층용은 PG 76-22를 목표로 아스팔트량의 3% 개질제와 혼합물의 0.1%에 해당하는 셀룰로스 화이버를 첨가하였다. 두 혼합물은 마샬안정도시험, 간접인장강도시험, 잔류간접인장강도시험, 휠트래킹시험 등을 수행하였다. 시험결과는 KS F 2349와 GR F 4005의 기준을 만족하였으며, 고품질재생아스팔트는 중교통도로의 표층 및 기층재료로 사용이 적합하였다. 현재 약 13,000톤의 고품질재생아스팔트 혼합물이 서울 올림픽 도로에 현장시공 되었다.

• 펄프종이기술
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• 제31권1호
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• pp.31-38
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• 1999

Adsorption of polymeric flocculants and dry strength agents onto the surface of papermaking fibers is critical for their effective utilization since the polymeric substances not adsorbed on fibers or fines keep recirculating in the papermaking system to cause various operational difficulties and loss of raw materials. Problems associated with the unadsorbed polymeric substances generate great attention because unprecedent interests in utilization of recycled papers and papermaking system closure. In this study, to understand the effects of recycling on the adsorption propensity of cationic polyacryamide (PAM) dry strength resin onto hardwood bleached kraft pulp fibers and fines a systematic approach was followed. Never dried bleached hardwood kraft pulp was recycled in two different ways. In mode one recycling experiment never dried pulp was beaten then recycled three times by employing simple drying and disintegrating steps. In mode two recycling experiment beating of the recycled pulp was carried out after each recycling step. Adsorption of cationic PAM on fibers and fines was evaluated employing Kjeldahl nitrogen analysis method. The influence of recycling on water retention value, carboxyl content, sheet density and tensile strength of the pulp was examined. As the number of recycling increased, water retention value of the fiber was reduced due to hornification and this in turn caused a decrease in adsorption of cationic PAM. On the other hand, the carboxyl content of the recycled fibers increased because of the oxidation of fibers occurred during drying, and this caused an increase in adsorption of cationic PAM. Because of these two opposing factors the adsorption of the cationic PAM on the recycled fibers decreased and then increased slightly at third recycling step. Increase of PAM adsorption, however, did not provide did not provide and strength improvement for the recycled pulp fibers indicating greater influence of the honification on interfiber bonding.

• 생물환경조절학회지
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• 제10권4호
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• pp.237-243
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• 2001

무가온 촉성재배시 멀칭재료가 참외 생육과 품질에 미치는 영향을 구명하기 위하여 토양 멀칭재료로 하우스외피복 재활용필름, 배색 P.E. 필름, 녹색 P.E. 필름과 대조구로 투명 P.E. 필름을 설치하여 지온의 변화와 생육, 과실품질 등을 조사하였다. 토양 5cm 깊이의 일.월중 지온은 하우스외피복 재활용필름에서 높았으나 광 투과율이 낮은 녹색 P.E필름에서 낮았다. 토양 심도별 야간지온은 녹색 P.E. 필름은 토양 깊이 20cm에서 나머지 필름은 토양 깊이 5cm에서 가장 높았으며, 멀칭 재료별 지온차는 깊이 내려갈수록 점차 감소되었다. 정식 후 30일의 초장과 절수는 지온이 높은 하우스외피복 재활용필름이 유의하게 높았으며, LAI, CGR, RGR도 높은 경향을 보였다. 정식 후 30일의 잡초 발생량은 큰 차이가 없었으나 정식 후 90일에는 투명 P.E.필름에서 많았다. 과실 수확은 하우스외피복 재활용필름에서 빨라 투명 P.E.필름보다 2일 단축되었으나, 과중, 과장, 당도 등 과실특성은 큰 차가 없었다. 하우스외피복 재활용필름에서 상품수량은 2,426kg.10a$^{-1}$로 투명 P.E. 필름보다 6% 증수되었다.

• 월간포장계
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• 통권348호
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• pp.48-53
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• 2022

• 한국소음진동공학회논문집
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• 제18권2호
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• pp.247-254
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• 2008

Resilient materials are generally used for the floating floors to reduce the floor impact sound. Dynamic stiffness of resilient material, which has the most to do with the floor impact sound reduction. The resilient materials available in Korea include EPS(styrofoam), recycled urethane types, EVA(ethylene vinylacetate) foam rubber, foam PE(polyethylene). glass fiber & rock wool, recycled tire, foam polypropylene. compressed polyester, and other synthetic materials. In this study, we tested dynamic stiffness of resilient material and floor impact sound reduction characteristic to a lot of kinds of resilient materials. It was found that dynamic stiffness of multi-layered damping material could be estimated if know value of each layer that compose whole structure. And the test showed that the amount of the heavy-weight impact sound reduction appeared by being influenced from this dynamic stiffness of resilient material. The dynamic stiffness looked like between other resilient materials, a similar to the amount of the heavy-weight impact sound reduction was shown.

• 콘크리트학회논문집
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• 제29권4호
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• pp.379-387
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• 2017

본 연구에서는 기존 PVA 섬유보강 시멘트 복합체(fiber-reinforced cementitious composites, FRCCs) 대비 성능유지 90% 이상을 목표로 하여 자원순환형 재료를 치환한 PVA FRCCs를 제조 및 개발하고자 하였다. 자원순환형 재료를 치환한 FRCCs의 압축, 휨 및 직접인장강도 시험을 통하여 역학적 특성을 분석하였으며, 이와 더불어 FRCCs의 제조단계에서 이산화탄소($CO_2$) 배출량을 국내 외 LCI 데이터베이스를 통하여 평가하였다. 실험을 통해 역학적 특성을 평가한 결과, 자원순환형 재료의 치환율이 증가함에 따라 압축, 휨 및 직접인장강도가 감소하는 경향으로 나타났다. $CO_2$ 배출량은 물결합재비(W/B)가 높고, 플라이 애시(FA)의 치환율이 높을수록 감소하는 것으로 나타났다. FA의 치환율이 증가함에 따라 결합재 지수($B_i$) 또한 증가하여 단위 강도(1 MPa)를 발휘하기 위한 결합재의 양이 보통 포틀랜드 시멘트보다 FA가 높은 것으로 나타났다. FRCCs의 성능을 유지하기 위해 설정된 목표치와 $CO_2$ 배출량을 동시에 고려해 볼 때 W/B 45%, FA 25% 및 순환 잔골재 25%가 치환된 배합이 가장 우수한 것으로 나타났다.

• 유기물자원화
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• 제20권2호
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• pp.27-35
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• 2012

건설폐기물 중 다량으로 발생하는 폐콘크리트는 현재 순환골재로 많이 사용되고 있다. 그러나 순환골재의 사용은 구조물로 사용되기 보다는 채움재나 성토재로 이용되고 있는 것이 현실이다. 폐콘크리트와 같은 순환골재가 구조물의 건축자재로 사용되기 위해서는 품질향상과 함께 가능한 많은 수요처를 확보하는 등의 적극적인 활성화방안이 필요하다. 본 연구에서는 국내 외 건설폐기물의 발생 및 처리, 재활용현황, 그리고 재활용에 관련된 제도 및 재활용을 저해하는 요인 등을 조사하여 이를 토대로 건설폐기물의 재활용 활성화 방안을 제시하였다.