Concrete is brittle under tensile loading and the mechanical properties of concrete may be improved by randomly oriented short discrete fibres which prevent or control initiation and propagation or coalescence of micro cracks. Ductility of concrete is provided with fibre reinforced cementations composites, because fibres bridge crack surfaces and delay the onset of the extension of localised crack. This paper presents experimental investigations mainly on mechanical properties of M30 grade of concrete considering water cement ratio 0.47. Glass fibre was added in green concrete by volume of concrete at variegated percentages from 0% to 0.4% with increment of 0.1%. Mechanical properties like compressive strength, flexural strength, indirect split tensile strength and modulus of elasticity along with ultrasonic pulse velocity were carried out. Slump is decreasing with the addition of glass fibres. The maximum increase in compressive strength is 32% and 13% at 7days and 28 days respectively. The flexural strength and split tensile strength increased up to 35% and 32% respectively over the range of glass fibre dosages. Modulus of elasticity increases significantly and higher value of it indicates the controlling factor of sudden failure. Ultrasonic pulse velocity result represents the quality of concrete. Concrete slab for rigid pavement was designed and found safe and economic thickness.
