|
Title |
Effect of Recycled Coarse Aggregate (RCA) Replacement Level on the Bond Behaviour between RCA Concrete and Deformed Rebars
|
|
Authors |
장용헌 ; 최기선 ; 유영찬 ; 김긍환 ; 윤현도 |
|
Keywords |
순환 굵은골재 ; 치환율 ; 부착강도 ; 뽑힘 recycled coarse aggregate(RCA) ; replacement level ; bond strength ; pull-out |
|
Abstract |
In this study, mixed recycled coarse aggregate (RCA) was produced by mixing RCA from waste concrete in order to evaluate a new method of RCA production. Bond strength between reinforcing bars and RCA concrete was qualitatively evaluated as a part of continuous studies to establish design code of reinforced concrete structural members using recycled aggregate. For practical application, specimens were manufactured with the ready mix RCA concrete. Parameters investigated include: concrete compressive strength (i.e 21, 27 and 40 MPa), replacement levels (i.e 0, 30, 60 and 100%), bar position (i.e vertical and horizontal) and bar location (75 and 225 mm). For the pull-out test, each specimen was in the form of a cube, with each side of 150 mm in length and a deformed bar, 16 mm in diameter, was embedded in the center of each specimen. From the test results, the most of HT type specimen with compressive strength of 21 and 27 MPa showed lower bond strength than the ones provided in CEB-FIP and considered in reinforcement location factor (α = 1.3). It was reasoned that bonded area of top bar specimen was reduced at the soffit of reinforcement because of bleed water of fresh concrete. Therefore the reinforcement location factor in current KCI design code should be reviewed and modified.
|