Optimal Mix Design Model of Recycled Aggregate Concrete for Artificial fishing Reefs

J. Ocean Eng. Technol. 2004;18(1):53-62.

인공어초용 재생골재 콘크리트의 최적 배합설계 모델

홍종현,김문훈,우광성,고성현

탐라대학교 토목환경공학과,탐라대학교 토목환경공학과,영남대학교 토목공학과,영남대학교 토목공학과

Keywords: Precast Artificial Fishing Reefs, Mix Design Model, Recycled Aggregate Concrete

핵심용어: 인공어초, 배합설계모델, 재생골재 콘크리트

Abstract

The Purpose of this study is to recycle the waste concrete, which is generated in huge quantities, from construction works. in order to achieve this goal, it is important to determine the compressive strength, workability, slump, and ultrasonic velocity of recycled aggregate concrete. Thus, several experiment parameters are considered, such as water-cement ratios, sand percentage, and fine aggregate composition ratios, in order to apply the recycled aggregate concrete to pre-cast artificial fishing reefs. From the results, it has been shown that the proper mix designs for reef concrete are W/C=45%, S/a=50%, SR50:SN50 in recycled sand and natural sand mix combination case, W/C=45%, S/a=50%, SC50:SN50 in crushed sand and natural sand mix combination case, W/C=45%, S/a=50%, SR50:SC50 in recycled sand and crushd sand mix combination case. Also, this study shows that the shape and surface roughness of fine aggregate particles have an effect on the strength, slump, ultrasonic velocity of tested concrete, and the compressive strength ratios of 7days' and 90days' curing ages of recycled aggregate concrete are about 70% and 110% of 28days' curing age.