Cyclic Flexural Behavior of Polypropylene and Sisal Fiber Reinforced Concrete

Abstract

This experimental research investigation aims to compare the cyclic behavior of concrete reinforced with discrete polypropylene and sisal fibers. Prismatic concrete specimens having dimensions of 550 x 150 x 150 mm were produced with concrete containing low alkaline content. Both fibers used were 51 mm long and were incorporated into fractions of 6 kg/m 3 and 10 kg/m 3 of polypropylene and sisal fiber, respectively. A cyclic three-point flexural test was conducted in notched beams based on recommendations of RILEM TC 89-FMT. All the composites presented deflection softening behavior and both fibers provided the same level of residual loads. The loading and unloading cycles resulted in degradation of stiffness with increasing CMOD, being more evident for concretes reinforced with polypropylene fiber. Some fracture parameters obtained from the cyclic tests showed that both composites presented similar fracture properties. 1.