Abstract
Ductile fiber reinforced cementitious composites（DFRCC）have been actively investigated. Although DFRCC shows a deflection hardening behavior with multiple cracking under the bending stress, the mechanical properties are influenced by the combination of composing materials such as fiber and matrix. The size of aggregate particles is expected to have a significant influence on the fracture properties of the matrix. The particle size of aggregate larger than the fiber spacing leads to balling and greater interaction of fibers in the paste. The increase in the particle size of aggregate makes it difficult to achieve a uniform dispersion of fibers.
Therefore, the purpose of this study is to evaluate the influence of particle size and volume of fine aggregate on the mechanical properties of DFRCC under four points bending tests as per JCI standard（JCI-S-003-2007）. In this study, natural river sand and two types of silica sand were used as the fine aggregate. Test parameters herein were fine aggregate size, water-cement ratio and sand-cement ratio. From the results of bending tests, the larger ultimate tensile strain value was obtained from a combination of lower W/C and S/C, and smaller particle size of sand. Furthermore, a larger number of cracks were observed from a combination of lower S/C and smaller particle size of sand.
