• 콘크리트학회논문집
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• 제17권5호
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• pp.785-792
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• 2005

본 연구는 굵은골재의 입형불량과 잔골재의 조립률 저하가 초유동콘크리트의 특성에 미치는 영향을 검토한 것이다. 이론 위해 잔골재 조립률을 2.0, 2.5, 3.0, 3.5로 변화시키고 굵은골재는 입형개선전$\cdot$후 골재를 사용하여 초유동콘크리트의 유동검 및 충전성능을 검토하였다. 또한 골재입자의 분산거리를 상대비교 함으로써 잔골재의 조립률 및 굵은골재의 입형이 골재입자의 분산거리에 미치는 영향을 검토하였다. 실험 결과 굵은골재와 잔골재 혼합시의 최소공극률은 골재 입형개선 유무에 관계없이 잔골재 조립률 3.0, 2.5, 2.0, 3.5 순으로 나타나 조립률 KS 규정 값 $2.3\~3.1$보다 작거나 클 경우 공극률을 증가시키는 것으로 나타났으며, 굵은골재의 입형은 구형율 0.69의 원반상에서 구형율 0.78의 구상으로 개선할 경우 최소공극률을 나타내는 잔골재율을 $47\%$에서 $41\%$로 $6\%$ 감소시키는 것으로 나타났다. 잔골재 조립률에 따른 28일 압축강도 특성은 조립률 2.0에서 2.5, 3.0으로 증가할수록 약 3MPa씩 증가하였으나, 조립률 3.5에서는 3.0에 비해 약 9MPa 정도 감소하였다. 또한 굵은골재의 입형개선과 잔골재 조립률의 증가는 유동성, 충전성 및 V로드 상대유하시간을 향상시키는 것으로 나타났으며, 잔골재 조립률은 KS 규정 값 $2.3\~3.1$을 만족하는 범위내에서 높은 값을 사용하는 것이 페이스트 용적비를 증가시키는 것으로 나타났다.

• 한국구조물진단유지관리공학회 논문집
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• 제15권3호
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• pp.178-185
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• 2011

본 연구는 강모래와 부순 모래를 일반적인 혼합방법과 아스팔트 골재 혼합에 사용되는 Driscoll 방법으로 각각 혼합하여 그 특성을 알아보고, Driscoll 방법의 콘크리트용 골재에 대한 적용성을 판단하고자 하였다. 이에 따라 일반혼합과 Driscoll 방법으로 혼합한 골재의 조립율 및 입도곡선, 굳지 않은 콘크리트의 특성 중 슬럼프와 공기량 및 굳은 콘크리트의 특성 중 28일 압축강도 시험을 통해 혼합방법의 따른 특성을 알아보고자 하였다. 아스팔트 골재의 혼합에 사용되는 Driscoll 방법을 사용하여 콘크리트 골재를 혼합하였을 때 일반적인 혼합방법과 비교하여 슬럼프, 공기량, 28일 압축강도가 오차수준 정도의 미미한의 차이를 나타내었다. 따라서 아스팔트 골재 혼합에 사용되는 Driscoll 방법은 콘크리트용 잔골재의 혼합에도 적용 가능할 것으로 판단된다.

• 한국건설순환자원학회논문집
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• 제7권2호
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• pp.123-130
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• 2019

본 연구에서는 순환잔골재의 혼입률에 따른 콘크리트의 강도 특성을 실험을 통해 확인하고, 전과정평가(LCA, Life Cycle Assessmet) 기법을 이용하여 순환잔골재의 전과정 환경영향을 평가하여, 콘크리트를 제조함에 있어서 순환잔골재 사용의 유효성을 확인하여 순환골재 콘크리트 활용을 위한 기초적 자료로 사용하는 것을 목적으로 한다. 이를 위해, 목표설계기준압축강도는 27MPa로 하였으며, 순환골재 실용화를 고려하여 순환잔골재의 혼입률을 0, 30, 60, 100%로 설정하여 굳지 않은 콘크리트 및 굳은 콘크리트에 대한 실험을 통해 슬럼프, 공기량, 압축강도 등을 확인하였고, 순환잔골재의 전과정 환경영향을 평가하고 타 골재와 환경영향을 비교 분석 하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.339-342
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• 2000

Recently, the importance of the conutermeasures for waste materials has pointed out. Waste glass is also one to waste materials used for the recycling in construction sites. The crushed waste glass has been used to make a glass polymer composite that can be applied for sewer, storm drain pipe and interlocking block, etc. In this study, the crushed waste glass is explored with the possibility of recycling it, as a substitute for fine aggregates. The prepose of this investigation is to improve the strengths and acid resistance of the UP mortars using crushed waste glass. The UP mortars are prepare with blast furnace slag fly ash filler. the UP-fine aggregate ratios the crushed waste glass replacements for fine aggregate are tested strengths before and after immersion(H (아래첨자2)SO(아래첨자4) 10%), weight change and acid resistance are also tested. From the test results, the relative strength or UP mortars using fly ash as filler are found to be somewhat superior to that of the UP mortars using blast furnace as filler, And a UP mortar with fly ash as a filler, a UP-fine aggregate ratio of 15% and a waste glass replacement if 50% for fine aggregate is recommended as optimal mix proportion of UP mortar using crushed waste glass. Accordingly, it is enough to assure the use of the crushed waare glass as an aggregate for the production of UP mortar.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.267-270
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• 2003

This study is intended to investigate the engineering properties of concrete, in which cement and fine aggregate are replaced with cement kiln dust(CKD), such as the properties of fresh concrete and hardened concrete and hydration heat history, for effective using method of CKD, a by-product produced in the process of making cement. According to the results, as the replacing ratio of CKD increases, slump and air content of concrete decreases remarkably due to an increase of viscosity and filling of the pores. As the properties of setting, initial and final setting time are shortened with an increase of the replacing ratio of CKD, and as the replacement of CKD for fine aggregate increases, setting time is shortened more greatly. Compressive strength increases due to filling of the pores and reduction of air content in comparison with plain concrete. When the replacement ratio of CKD for cement is 10% and 15%, peak temperature of hydration heat lowers slightly, but it goes up in the case of replacement of CKD for fine aggregate. Also, when cement and fine aggregate is replaced with CKD by 2.5% and 7.5% respectively(1C3S) in the case of replacement of CKD for cement and fine aggregate, it is highest.

• Advances in concrete construction
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• 제16권3호
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• pp.141-153
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• 2023

In order to develop and take full advantage of pasture fiber and waste concrete, this article studied how different amounts of pasture fiber influenced the toughness and pore structure of concrete with different replacement rates of recycled fine aggregate. Pasture fiber recycled concrete constitutive equations were established under idealized stiffness and toughness damage rate, based on fracture energy and damage mechanics theories. The relationship between pore structure and toughness was studied utilizing nuclear magnetic resonance and fractal theory. The toughness of text groups (0% (JZ), 10% (ZS10), 20% (ZS20)) first increased and then decreased with increasing amounts of pasture fiber, based on the damage rate of toughness. The toughness of concrete samples with recycled fine aggregate and pasture fiber is negatively correlated to the fractal dimension of small and medium-sized pores with a pore size of 0-500 nm. At a replacement rate of 10% of the recycled fine aggregate, the fractal dimension of the air voids (r: 500-9000 nm, i.e., Lg(r) ∈ [2.7, 3.9]) shows a gradual decrease with the increase of grass fiber dosage, indicating that with such a replacement rate of the recycled fine aggregate, the increase of pasture fiber can reduce the complexity of the pore structure of the air voids (500-9000 nm).

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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• pp.342-349
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• 1998

The objective of this study is to investigate the characteristic change of antiwashout underwater concrete with variation of blend ratio of sea sand and fine aggregate percentage through experimental researches. According to the experiments results, when sea sand are mixed in antiwashout underwater concrete mixture by about 40% per total fine aggregate, in fine aggregate percentage of 40%, it is found that the flowability fit and the compressive strength is higher others.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.303-306
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• 1997

In this paper, we carried out the fundamental experiments on the resistance of chemical attack of mortar using the electric arc furnace slag as fine aggregate. The mortar specimens made from the electric arc furnace slag (EAF slag) as fine aggregate were immersed in artificial seawater and two sorts of chemical solutions, and measured to investigate the change of compressive strength and weight.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.225-226
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• 2016

Bottom ash generated in thermoelectric power plants could be used as substitutional fine aggregate such as pearlite of fireproof mortar due to its lightweight and porosity. Development of substitutional materials is necessary because pearlite has several problems such as production of carbon dioxide during manufacturing process and high price. This study is to confirm the possibility of air cooling process bottom ash for fireproof mortar as substitutional material of pearlite through basic experiment.

• 한국건축시공학회지
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• 제9권1호
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• pp.81-87
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• 2009

The purpose of this study is to investigate the sulfate attack resistance of concrete using the EAF(electric arc furnace) Slag as fine aggregate. In order to figure out the effects of magnesium sulfate solution on the durability of concrete using the EAF Slag as fine aggregate, the experiments for the immerging test in the 10% magnesium sulfate solution was executed by selecting factors such as aging processes, replacement ratio(0, 10, 20, 30, 50%), and duration of immerging. The specimens were made with various EAF slag replacements for fine aggregates and with W/C ratio fixed 0.45. compressive strength and S.D.F(Sulfate Deterioration Factor), weight change, and SEM(Scanning Electron Microscope) were tested. From the test results, EAF slag aggregate treated with accelerated aging is better than treated with air aging. The compressive strength and resistance to the sulfate attack is slightly improved with an increase in the EAF slag aggregate treated with accelerated aging replacement for aggregate.