STUDY ON PERFORMANCES OF STEEL FIBER REINFORCED C55 GRADE SELF-COMPACTING CONCRETE

Based on the requirement for the construction application of high strength steel fiber reinforced self-compacting concrete (SFR-SCC) to the composite joint section between steel and concrete box girders of the super-long span hybrid girder cable-stayed bridge in the Edong Yangtze River, the effect of the volume fractions of short steel fiber on the workability and compressive strength of C55 grade SFR-SCC was investigated, and the differences in the mechanical properties, crack resistance, flexural toughness and durability between the C55 grade SFR-SCC and normal C55 grade SCC were tested. The results indicated that the incorporation of 0.6 similar to 0.8vol% steel fiber significantly increased the compressive strength of the SFR-SCC, and didn't affect the non-vibration compressive strength while meeting the self-compacting. Furthermore, the 0.6vol% steel fiber significantly increased the split tensile strength, flexural strength and elastic modulus, and decreased the sensitivity of plastic shrinkage crack and drying shrinkage value as well as enhanced the toughness of the SFR-SCC. Moreover, the SFR-SCC has high chloride penetration resistance and freeze-thaw durability.