Title Effects of Aggregate Size and Fiber Volume Fraction on Flexural Properties of Steel Fiber Reinforced Concrete (SFRC)
Authors Jang, Seok-Joon ; Ahn, Kyung-Lim ; Yun, Hyun-Do
DOI http://dx.doi.org/10.5659/JAIK_SC.2015.31.2.45
Page pp.45-54
ISSN 12269107
Keywords Flexural ; toughness ; Aggregate size ; Fiber volume fraction ; Fiber dispersion
Abstract This paper describes the effect of aggregate size and fiber volume fraction on flexural properties of steel fiber reinforced concrete(SFRC) with specified compressive strength of 60 MPa. Maximum aggregate size used was 8 and 20mm, and steel fiber volume fraction was 0, 0.5, 1, 1.5, 2% in volume basis, in this study. Flexural properties studied include first-crack strength, flexural strength and toughness index of hardened SFRC. For this purposes, three prisms (100×100×400 mm) form each mixture were made and tested under four points bending on the span length 300 mm. Test results indicated that flexural strength and toughness of SFRC were improved with increasing the volume fraction. Especially, specimens with aggregate size of 8mm were reported higher improvement in flexural toughness index than those with 20mm. This phenomenon are remarkable that fiber dispersion is improved with smaller aggregate size. Also the optimum volume fraction of SFRC was presented for that with 1.5% volume fraction. Based on test results and available literatures, flexural strength prediction model was established from compressive strength, volume fraction and aspect ratio of steel fiber. The model existed a good correlation between measured data.