Comparison of Flexural Performance of Lightweight Fibre-reinforced Concrete and Normalweight Fibre-reinforced Concrete

Abstract

Current study encompasses comparison of flexural tests results of Normalweight Fibre-reinforced Concrete (NWFC) and Lightweight Fibre-reinforced Concrete (LWFC) beam specimens. Fibres are known for their positive effect on crack control, better post-cracking behaviour under flexure and for enhancing toughness. These improvements, however, come at the expense of degraded workability. Using lightweight aggregates of regular shape instead of heavier, irregular and rough textured normalweight aggregates can address the issue of poor workability of concrete besides other advantages that it will bring along with. Replacing normalweight aggregate with lightweight aggregate also has its demerits and in most cases under similar testing environments lightweight concrete has lower strength results. This paper covers evaluation of flexural performance for both LWFC and NWFC having similar compressive strength class. For this purpose 24 beams 150 × 150 × 700 mm in dimensions were tested under flexure. For a fair comparison, it was made sure that both the concretes (LWFC and NWFC) at every fibre volume fraction (0, 0.25, 0.5 and 0.75%) fell under the same strength class.