• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.605-608
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• 2006

The purpose of this research is to develop the fireproofing mortar through the improved fireproofing properties. Therefore, after manufactured the mortor by changing the mixture rate of the perlite(PL) in three level, we investigated air content, flow value and compressive strength. As a result of this research, as the mixture rate was increased and the air content was also increased. But the flow ability and the compressive strength of the mortar were comparably decreased. Beside, we also found that there is efficiency of the lightweight by mixed PL.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.190-195
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• 1997

The purpose of this study was to use daily waste incinerated ash, which was reclaimed worthlessly, as substitutes of fine aggregates in concrete. Various kinds of admixture was utilized to strengthen the cement mortar mixed with waste incinerated ash, and altered the curing condition to diminish the rate of expansion. By the results of this experiment, it was possible to produce the lightweight concrete, charactered with the gravity below 1.5 and over 160kg/$\textrm{cm}^2$ compressive strength by replacing all fine aggregates with waste incinerated ash. It was also observed that the low temperature curing condition, lessoned gas exhausts, was effective to increase the strength of cement mortar.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.71-72
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• 2017

The oyster shell is lightweight and exhibits strength characteristics similar to sand. In this study, mortar specimens were fabricated by crushing them and processed to 5mm or less of the fine aggregate standard, and examined the fire resistance of the mortar according to changes in particle size distribution. In this experiment, seven particle size distribution conditions were tested. In addition, the mixing ratio was fixed at 1: 3, and the experiment was conducted in terms of the volume ratio because the densities of sand and oyster shells were different.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.139-140
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• 2023

This study aims to determine the microstructural characteristics of waste glass beads, a lightweight aggregate manufactured from waste glass powder, when incorporated into mortar in order to examine its usability depending on the particle shape.

• 한국건설순환자원학회논문집
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• 제11권3호
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• pp.210-217
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• 2023

Various performances of ultra-high performance concrete (UHPC) applied with microplastics and expanded polystyrene (EPS) beads were evaluated. CompressIve and flexural strength, performance after ignition, flow-down in fresh state, and effective bond strength were evaluated. Designed weight of the cement panel with these mixtures was calculated based on the flexural strength. As a result of the experiments, it was confirmed that the EPS could reduce the density of UHPC with largest range. By maximum addition of EPS beeds, the density of UHPC decreased to 1300 kg/m³, and the compressive and flexural strengths for this mixtures were in ranges of 20-30 MPa and 15-20 MPa, respectively. On the other hand, lightest cement panel could be designed with UHPC having a density ranges about 2.0 g/cm³.

• 콘크리트학회지
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• 제10권6호
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• pp.191-202
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• 1998

콘크리트의 강도발현을 양생온도와 재령의 함수로 나타내는 적산온도 방법은 시멘트 콘크리트의 강도추정에 폭넓게 사용되어 왔다. 본 연구에서는 열경화성인 불포화 폴리에스터 수지를 결합재로 한 경량 폴리머 모르터를 대상으로 하여 적산온도법에 의한 초기강도 추정방법을 구명하였다. 폴리머 모르터의 압축강도는 가사시간 및 강도발현성에 영향을 미치는 촉매 및 촉진제 첨가량을 변화시켜 실험하였으며, 또한 적산온도 이론식에 사용되는 기준온도를 산출하였다. 적산온도는 추정된 기준온도를 적용시킨 적산온도 이론식에의해 산출하였으며 경량폴리머 모르터의 압축강도는 적산온도-압축강도의 관계로부터 추정할 수 있었다. 이 연구에서 얻어진 적산온도법에 의한 경량 폴리머 모르터의 강도추정식은 열경화성 수지를 이용한 각종 폴리머 모르터나 콘크리트에도 적용가능할 것으로 판단된다.

• Earthquakes and Structures
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• 제9권6호
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• pp.1273-1290
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• 2015

JK wall is a shear wall made of lightweight EPS mortar and reinforced with a 3-D galvanized steel mesh, called JK panel, and truss-like stiffeners, called JK stiffeners. Earlier studies have shown that low strength lightweight concrete has the potential to be used in structural elements. In this study, seismic contribution of the JK infill walls surrounded by steel frames is numerically investigated. Adopting a hybrid numerical model, behavior envelop of the wall is derived from the general purpose finite element software, Abaqus. Obtained backbone would be implemented in the professional analytical software, SAP2000, in which through calibrated hysteretic parameters, cyclic behavior of the JK infill can be simulated. Through comparison with earlier experimental results, it turned out that the proposed hybrid modeling can simulate monotonic and cyclic behavior of JK walls with good accuracy. JK infills have a panel-type configuration which their dominant failure mode would be ductile in flexure. Finally technical and economical advantages of the proposed JK infills are assessed for two representative multistory buildings. It is revealed that JK infills can reduce maximum inter-story drifts as well as residual drifts at the expense of minor increase in the developed base shear.

• KIEAE Journal
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• 제10권3호
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• pp.89-96
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• 2010

In comparison with ordinary or heavy-weight concrete, light-weight air void concrete has the good aspects in optimizing super tall structure systems for the process of design considering wind load and seismic load by lightening total dead load of buildings and reducing natural resources used. Light-weight air void concrete has excellent properties of heat and sound insulating due to its high amount porosity of air voids. So, it has been used as partition walls and the floor of Ondol which is the traditional Korean floor heating system. Under the condition of which the supply of light-weight aggregates are limited, the development of light-weight concrete using air voids is highly required in the aspects of reduced manufacturing prices and mass production. In this study, we investigated the physical properties and thermal behaviors of specimens that applied different mixing ratios of foaming agent to evaluate the possibility of use in the structural elements. We proposed the estimating equation for compressive strength of each mix having different ratio of foaming agent. We also confirmed that the density of cement matrix is decreased as the mixing amount of foaming agent increase up to 0.6% of foaming agent mixing ratio which was observed by SEM. Based on porosity and compressive strength of control mortar without foaming agent, we built the estimating equations of compressive strength for mortars with foaming agent. The upper limit of use in foaming agent is about 0.6% of the binder amount. Each air void is independent, and size of voids range from 50 to $100{\mu}m$.

• 한국건설순환자원학회논문집
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• 제3권4호
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• pp.342-347
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• 2015

본 연구는 최근 산업 발전으로 나날이 증가하는 폐타이어가 야기시키는 환경오염을 해결하고 폐타이어를 재활용함으로써 무분별한 매립을 예방하기 위한 기초 실험이다. 건축 재료의 경량골재를 폐타이어분말로 대체함으로써 폐타이어분말의 경량성을 검토하고 폐타이어분말의 재활용 계획을 제시하고 적용하고자 한다. 선행실험으로 폐타이어분말을 20, 40, 60, 80, 100(%) 등으로 치환하여 실행하였고, 측정 항목은 강도와 밀도이다. 본 실험은 선행실험을 기초로 하여 폐타이어 치환율을 15, 20, 25(%) 등으로 하였다. 폐타이어 골재의 입도는 0.2, 0.8, 1~2, 3~5, 5~7(mm) 등으로 고정하였다. 실험 결과 폐타이어 입도 1~2mm, 치환율 15%가 가장 적정한 입자크기 및 치환율 값을 나타내었다.

• 한국건설순환자원학회논문집
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• 제7권2호
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• pp.84-90
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• 2012

폐목재의 활용에 관한 특허동향 분석을 위해 한국특허정보원의 특허정보검색서비스(KIPRIS)에서 관련 키워드로 한국, 미국 및 일본의 특허 검색을 실시하여 2011년 12일 31일까지 특허 등록된 한국 77건, 미국 316건 및 일본 317건의 특허 자료를 수집하였다. 수집된 자료 중 거절, 소멸, 무효, 취하, 포기 및 폐목재와 관련이 적은 내용의 특허를 제외시키고 얻은 한국특허 71건, 미국특허 216건, 일본특허 227건에 대한 분석을 실시하였다. 또한 폐목재를 콘크리트용 경량골재로 활용하기 위한 기초 연구로서 파쇄시킨 소나무 임목부산물을 No. 8(2.4 mm)체로 쳐서 이를 통과시킨 것을 $100{\pm}5^{\circ}C$에서 24시간 동안 건조시킨 다음 잔골재의 일부로서 대체 사용한 모르타르 물성 실험을 실시하였다. 목재와 시멘트를 혼합하는 경우 목재의 수종과 부위에 따라서는 시멘트의 경화를 저해하는 것으로 알려져 있기 때문에 본 연구에서는 파쇄폐목재를 $20^{\circ}C$, $50^{\circ}C$, $80^{\circ}C$ 및 $100^{\circ}C$의 수중에서 일정 시간 동안 침지시킨 후 건조시킨 다음 이를 사용한 모르타르의 물성실험을 실시하여 파쇄폐목재의 전처리 효과를 함께 고찰하였다.