The flexural toughness of high strength fiber reinforced concrete with styrene-butadiene latex

摘要

Styrene-butadiene latex was used to produce a concrete matrix with a compressive strengthranging from 65 to 85 MPa; 28 groups of high strength concrete beam specimens were cast with differentcombinations of this latex and three fiber types: a deformed steel fiber, a high density polypropylene fiber (HPP)and an un-fibrillated fiber with blended polypropylene and polyethylene components. These specimens weretested in four-point bending, and results were analyzed following the JSCE-SF-4 procedure.Fiber type, fiber volume fraction and latex content all had a strong influence on toughness characteristics.The mix with 10% latex and 1.0% of steel fibers showed optimum toughness, and its load-deflection curveexhibited strain hardening after the first cracking of the beam. An attempt was made to characterize the synergybetween the fibers and the latex over a wider range of deflections. Synergistic effects were observed in almostall composites when the latex content was at the optimized dosage (10%), but steel fibers appeared to be morecompatible than the synthetic fibers in the latex modified concrete in terms of both load-carrying capacity andtoughness. Considering its other properties, such as excellent bonding properties and durability, it is concludedthat this high performance composite could be a promising material for both structural and repair purposes.