To improve the initial strength and stability of lightweight-foamed concrete, which shows suitable sound absorption and insulation characteristics, the effect of CO2-reduced cement on the properties of the concrete was investigated. Various mixing ratios were applied by substituting a certain amount of slag and Calcium Sulfo Aluminate (CSA) in CO2-reduced Ordinary Portland Cement (OPC) and the physical properties of the samples were examined using the Korean Standard. The kiln temperatures of the CSA were 100–200°C ; these values are lower than those of OPC and can lead to energy saving. In addition, the low limestone content reduces greenhouse gas emissions by 20 %. Adding a small amount of CSA in OPC content activates Ca-Al-H2-based hydrates, and the initial compressive strength of the concrete is improved. As the CSA content increased, the thermal conductivity of the concrete decreased by up to 8% compared to plain concrete, thus indicating an improvement in its insulation. Therefore, the settlement stability was improved as the addition of CSA shortened the setting time.

This study investigated the properties of lightweight foamed concrete by using surfactant and synthetic foaming agent, lightweight aggregate. The effects of foaming agent types and replacing ratio of lightweight aggregate on the compressive strength, density and pore structure of the concrete were investigated. This study showed the improvement of important properties of lightweight foamed concrete. Lower pore distribution and correspondingly higher compressive strength values were reached. Also, synthetic foaming agent had more positive effect on the strength of foamed concrete.

This study investigated the properties of foamed concrete by using surfactant foaming agent and synthetic foaming agent. The effects of foaming agent types on the compressive strength, density and pore structure of the concrete were investigated. The samples were assessed by XRD analysis and simultaneous SEM was used to study their pore distribution. This study showed the improvement of important properties of foamed concrete. Lower pore distribution and correspondingly higher compressive strength values were reached. Also, synthetic foaming agent had more positive effect on the strength of foamed concrete.

This study investigated the properties of foamed concrete by using surfactant foaming agent and synthetic foaming agent. The effects of foaming agent types on the compressive strength, density and pore structure of the concrete were investigated. The samples were assessed by XRD analysis and simultaneous SEM was used to study their pore distribution. This study showed the improvement of important properties of foamed concrete. Lower pore distribution and correspondingly higher compressive strength values were reached. Also, synthetic foaming agent had more positive effect on the strength of foamed concrete

In this study, natural fine aggregates(NFA) and recycled fine aggregates(RFA) was applying in the lightweight foamed concrete. To replacement of OPC, high volume blast furnace slag was used and incineration ash and recycled aggregates powder were used as alrali activator, Fundamental performances of lightweight famed concrete has been tested. Results showed that as the increase of foam conduction ratio, the strength and the density has been decreased

본 연구는 실험계획법을 통하여 과산화수소로 발포된 석고 혼입 경량기포콘크리트로 통계적 분석을 실시하였다. 본 실험에서는 경량기 포콘크리트를 구성하는 각 재료의 혼합비율을 실험인자로 설정하고, 실험을 통해 얻어진 반응변수에 대한 통계적 분석으로 역학적 특성을 평가 하였다. 실험인자는 석고혼입율, 물결합재비 및 발포제첨가비 이며, 반응변수는 겉보기밀도, 압축강도, 휨강도이다. 경량기포콘크리트의 배합은 반응표면설계의 Box-Behnken (B-B)계획법에 의해 총 15회의 실험점을 설정하였다. 본 연구결과 다음과 같은 결론을 얻었다. 반응변수에 대한 각 설명인자 (석고혼입율, 물결합재비, 발포제첨가비)의 유의확률값은 유의수준 α=0.05에서 유의한 것으로 추정되었다. 경량기포콘크리트의 겉보기밀도에 대한 반응표면 분석 결과, 물결합재비 와 발포제첨가비만 유의 (α=0.05)한 것으로 추정되었으며, 겉보기밀도와 기포량 및 함수율과의 관계는 반비례함을 확인 알 수 있었다. 경량기포콘크리트의 압축강도에 대한 반응표면 분석 결과, 물결합재비, 발포제첨가비 및 발포제첨가비의 제곱항이 유의 (α=0.05)한 것으로 추정되었다. 경량기포콘크리트의 휨강도에 대한 반응표면 분석 결과, 물결합재비 와 발포제첨가비만 유의 (α=0.05)한 것으로 추정되었다. 다중 반응 최적법을 통해 반응변수들의 목표값을 만족하는 최적조건 영역을 확인할 수 있었다.

최근 저탄소 녹색성장이 대두되면서 정시적이고 안정적인 수송체제로서 철도의 관심이 고조되고 고속철도 및 신선철도 등 철도의 건설이 지속적으로 진행되고 있으며 이에 따라 연약지반 위에 철도노반을 건설하는 사례가 증가하고 있다. 본 연구에서는 부전-마산 복선전철사업 중 연약지반 상에 경량기포콘크리트를 이용한 piled-raft 공법의 철도노반 적용성에 관하여 실내실험 및 수치해석을 통하여 검증하였다. 수치해석 결과 압축강도 7MPa, 인장강도 0.35MPa, 휨강도 3.2MPa의 결과를 얻었으며, 말뚝간격 2.5D, 3.5D에 따라서 1.1배 차이가 나타났다. 경량기포콘크리트를 이용한 piled-raft 공법을 철도노반에 적용할 경우 충분한 안정성을 확보할 수 있었고, 말뚝간격은 3.5D로 시공할 경우 충분한 안정성 및 경제성을 확보할 수 있었다.