| Title |
A Study on the Properties and Mix Design of Eco-friendly Concrete Bricks Using Recycled Fine Aggregates |
| Authors |
Choi, Hyungkook ; Yang, Sungchul ; Son, Jaeho ; Lee, Seunghyun |
| DOI |
https://dx.doi.org/10.6106/KJCEM.2024.25.5.032 |
| Keywords |
Recycled Fine Aggregate; Concrete Brick; Mix Design; Physical Performance |
| Abstract |
In the construction industry, lack of reliability in the quality of recycled aggregates, harmful substance problems, and negative consumer perceptions limit the expansion of the use of recycled aggregates. In this respect, existing studies mainly focus on the use of recycled coarse aggregates in concrete in consideration of durability. On the other hand, in the case of recycled fine aggregates, not only are there insufficient cases applied to major structures, but the scope of application is very limited due to lack of awareness. Therefore, the main purpose of this study is to present the possibility of their application in bearing and non-bearing wall structures through physical characteristics experiments of concrete bricks for masonry according to various mixing ratios of recycled fine aggregates and cement amounts. To this end, the compressive strength and absorption rate of concrete bricks were measured focusing on the mixing ratio of the recycled fine aggregate and the crushed fine aggregate and the amount of cement. As a result, it is found that it is possible to use 100% of recycled fine aggregate for 200㎏/㎥ of cement or 25% of crushed fine aggregate mixed with 75% of recycled fine aggregate for the same amount of cement to achieve the compressive strength of 13㎫, witch is one of the quality requirements for concrete bricks for bearing walls. In addition, it is found that to meet the strength of 8㎫, one of the quality requirements for non-bearing walls, it is sufficient to use 100% of the recycled fine aggregate for 100㎏/㎥ of cement. Through the absorption rate tests, it is also confirmed that the absorption rate of the concrete brick is 13% or less by meeting the required performance criteria. This means that even if recycled fine aggregate is used in the manufacture of concrete bricks, the quality standards required by KS F 4004 (concrete bricks) can be sufficiently met. |