Mechanical Properties and Stress-Strain Behaviour of Self Compacting Concrete with and Without Glass Fibres

The development of Self Compacting Concrete marks an important milestone inimproving the product quality and efficiency of the building industry. Self CompactingConcrete is a recently developed concept in which the ingredients of the concrete mix are proportioned in such a way that it can flow under its own weight to completely fill theformwork and passes through the congested reinforcement without segregation and selfconsolidate without any mechanical vibration. Several studies in the past have revealedthe usefulness of fibres to improve the structural properties of concrete like ductility,post crack resistance, energy absorption capacity etc. Fiber reinforced self compactingconcreting combines the benefits of self compacting concrete in fresh state and shows animproved performance in the hardened state due to the addition of fibers. In thisinvestigation Cem-FIL anti-crack high dispersion glass fibres were added to selfcompacting concrete and Glass Fibre Reinforced Self Compacting Concrete wasdeveloped. An attempt has been made to study mechanical properties and stress-strainbehaviour of self compacting concrete and glass fibre reinforced self compactingconcrete. A strength based mix proportion of self compacting concrete was arrived basedon Nan-Su method of mix design and the proportion was fine tuned by using Okamura’sguidelines. Five self compacting concrete mixes with different mineral admixtures like flyash, ground granulated blast furnace slag and rice husk ash were taken for investigationwith and without incorporating glass fibres. A marginal improvement in the ultimatestrength was observed due to the addition of glass fibres to the self compacting concretemix. Also incorporation of glass fibres had enhanced the ductility of self compactingconcrete. Complete Stress-Strain behaviour has been presented and an empirical equationis proposed to predict the behaviour of such concrete under compression.