ASSESSING THE EFFECT OF DIFFERENT FIBERS ON SHEAR STRENGTH OF REINFORCED CONCRETE MEMBERS

Abstract

Concrete is the most widely used building material in the world. The single largest limitation of concrete is its weak and brittle nature under tensile stress. To improve concrete behavior, reinforcement materials that are strong in tension are embedded into the concrete to avoid brittle failure and increase tensile capacity. Besides the traditional methods of embedding continuous aligned reinforcement in anticipated zones of tensile stress, random discrete fibers can be dispersed into the concrete during the mixing procedure to create a composite material called fiber reinforced concrete (FRC). Distinctive fiber filaments are used to improve the ductility and strain-hardening of cementitious composite mortars and grouts. Fibers vary commercially and environmentally so that polyvinyl alcohol (PVA) fibers are relatively expensive and might have higher environmental impact than Portland cement, polypropylene (PP), steel, basalt, and glass. Limited studies compared the effects of different fibers (PVA, PP, basalt, steel, and glass) on the hardened mechanical properties of normal-strength concrete mixtures, and on the behavior of structural members cast with such concrete mixtures. A multiphase research program has been designed to address the above objectives and the aim of the phase presented in this thesis is to test the performance of fiber reinforced concrete in the context of shear structural behavior and mechanical properties. It was noticed that shear strength is the most affected parameter when introducing fibers to concrete. Thus, this research work aims at assessing the performance and explaining the effect of using seven different types of fibers on shear strength and crack width in cast beams.