• Title/Summary/Keyword: 친환경콘크리트

Search Result 186, Processing Time 0.023 seconds

The Fundamental Properties of Foamed Concrete as the Eco-friendly Ground Repair System for Cast in Site Using the CSA (CSA를 사용한 친환경 지반보수용 현장 기포콘크리트의 기초 특성 검토)

  • Woo, Yang-Yi;Park, Keun-Bae;Ma, Young;Song, Hun-Young
    • Resources Recycling
    • /
    • v.29 no.1
    • /
    • pp.53-61
    • /
    • 2020
  • This study aimed to develop a foam concrete material for a ground repair system that has low strength and low fluidity by using an eco-friendly binder, which substitutes industrial by-products for more than 90% of cement. Basic properties were evaluated after substituting a small amount of calcium sulfo aluminate (CSA) for the binder to improve the sinking depth rate and volume change, commonly found when it had a large amount of industrial by-products. The substitution rates of CSA for the eco-friendly binder used for the foam concrete were 2.5, 5, and 10%. Fresh properties, hardened properties, pore structure, and hydrates were analyzed. Experimental results showed that using only 2.5% of CSA could improve the deep sinking depth which occurred when using an eco-friendly binder. As a result, the weight difference between the upper, middle, and lower parts of cast specimens was improved even after being hardened. The addition of CSA also contributed to the formation of small, uniformly sized closed pores and improved initial strength. However, when the proportion of CSA increased, the long-term strength decreased. However, it satisfied the target strength when 5% or less of CSA was used. The results of this study revealed that it was possible to manufacture foam concrete with low strength and high fluidity for repairing ground satisfying target qualities by adding 2.5% of CSA to the eco-friendly binder containing a large amount of industrial by-products.

Study on the Optimal Mix Proportions of Lightweight Foam Concrete for Substitution of ALC (ALC 대체를 위한 선발포 경량기포콘크리트의 최적배합 선정 연구)

  • Choi, Sun-Mi;Kim, Beom-Soo;Kim, Jin-Man
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2023.05a
    • /
    • pp.199-200
    • /
    • 2023
  • This paper presents a study on the selection of optimal mix proportions for producing lightweight pre-foam concrete as a substitute for Autoclaved Lightweight Concrete (ALC) without the accelerated curing. The study was conducted using a rapid hardening binder made from by-products of the steel industry as the primary raw material. The experimental results established the optimal mix proportions, which included retarder content, water/binder ratio, foam content, and fiber inclusion amount, for the production of lightweight foam concrete. The optimal mix proportion was determined to have a retarder content at the minimum amount required to secure the working time, W/B of 35%, a foam content limited to 65% or less, and a fiber inclusion amount of 0.05% or less.

  • PDF

An experimental study on shrinkage and crack resistance of Hwang Toh concrete mixed with PET fiber (PET보강섬유를 혼입한 황토콘크리트의 건조수축 및 균열저항성에 관한 실험적 연구)

  • Kim, Hyun-Young;Kim, Sung-Bae;Yi, Na-Hyun;Han, Byung-Goo;Kim, Jang-Ho
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2008.04a
    • /
    • pp.797-800
    • /
    • 2008
  • To decrease the usage of cement, the pozzolan reaction materials are used as a mineral admixture. Hwang Toh which is broadly deposited in Korea is well known as a environment friendly material and the activated Hwang Toh which has the property of pozzolan reaction is practically used as a mineral admixture of concrete. PET fiber which is made by recycled PET bottle controls micro crack in concrete. But the study about concrete mixed with reinforcing fiber is not enough and the property of Hwang Toh concrete mixed with PET fiber is more complicated case. So this study performed drying shrinkage experiment to analyse mechanical property of Hwang Toh concrete mixed with PET fiber.

  • PDF

Practical Application of GGBS-Based Alkali-Activated Binder to Secondary Products of Concrete (고로슬래그 기반 알카리 활성 결합재의 콘크리트 2차 제품 적용성 평가)

  • Sim, Jae-Il;Yang, Keun-Hyeok
    • Journal of the Korea Institute of Building Construction
    • /
    • v.10 no.5
    • /
    • pp.37-44
    • /
    • 2010
  • This study examined the practical application of ground granulated blast-furnace slag (GGBS) based alkali-activated (AA) binders for the development of cementless environmental-friendly secondary products of concrete, such as brick, shore protection blocks and interlocking blocks. The addition amount and type of alkaline ion to activate GGBS varied according to the diverse qualities of the secondary products of concrete required in Korean industrial standards (KS) and other specifications. Test results showed that the secondary products of concrete using GGBS-based AA binders surpassed the demanded capacities of KS and other specifications. In addition, shore protection block had a pH value close to neutral, enabling an advantageous environment for marine life. Therefore, the GGBS-based AA binders can be effectively applied to develop eco-friendly secondary products of concrete with reduced $CO_2$.

A Study on the Eco-Friendly Durable Pre-Painting for Concrete Structure (콘크리트 구조물의 친환경 내구성 도장에 관한 기초 연구)

  • Jo, Byung Wan;Choi, Ji Sun;Lee, Seong Won
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.17 no.2
    • /
    • pp.110-116
    • /
    • 2013
  • A concrete structure has become bigger and higher because of development of construction technology and a change in construction environment. Also it tends to focus on repairing, reinforcement and exterior in harmony with environment for structure maintenance and performance improvement. The research is about eco friendly durable painting applicable to concrete structure using civil and architecture. it purpose to improve external beauties and durable problems due to flexibility by variation of temperature, adhesion of exterior wall, crack and delamination in existing organic and mineral painting. For those problems, we made a eco friendly pre-paint that is made with preliminary treatment mixture as a highly enriched waterproof agent and adhesive increasing agent in preprocessing mixture. Then we performed an experiment on durability of prevention neutralization of concrete, durability abrasion, hiding power, adhesion, temperature resistance and resistance to chemical attack. The result of an experiment shows that hiding power is over 0.96 in standard test, durability abrasion test got higher value 1mg than water paint 75mg and tensile strength is 6 times higher than standard waterproof specification.

A Study on the Selection of Expansion-Causing Substances for the Use of Converter Slag as Aggregate for Concrete (전로슬래그의 콘크리트용 골재로서 활용을 위한 팽창유발 물질 선별 연구)

  • Choi, Sun-Mi;Ra, Jeong-Min;Kang, In-Gyu;An, Tae-Yun;Kim, Jin-Man
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2022.11a
    • /
    • pp.87-88
    • /
    • 2022
  • The use of converter slag as an aggregate for concrete is limited due to the risk of expansion. This study analyzed the substances causing the expansion of converter slag and evaluated the possibility of its use as an aggregate for concrete through separation and selection. As a result of the experiment, it was confirmed that CaO and MgO were concentrated in the slag particles inducing expansion, and it was confirmed that it was possible to separate them from non-expanded particles through magnetic.

  • PDF