ENHANCEMENTOF MECHANICAL PROPERTIES OF LIGHTWEIGHT HYBRID FIBRE REINFORCED CONCRETE (LWHFRC)

Many research works has been carried out on concrete which had encouraged the development of material with replacement of aggregate in order to reduce their weight which resulted in lightweight concrete. For lightweight concrete, weight of the aggregate should be reduced so that the self weight of the structural members is reduced and helps in constructing of larger precast units where reduction of self weight is an important factor which may increases thermal insulation .Fibre reinforced concrete(FRC) is a concrete consists of fibrous material which increases the tensile strength of the concrete members with distributed and oriented fibres. In this investigation the strength and durability properties of lightweight concrete by replacement of light weight aggregates will be studied and also discussed 4 types of lightweight aggregates. The properties of conventional concrete are compared with properties of light weight FRC . An optimum control mix is designed based on light weight concrete using the light weight aggregates and mechanical behaviour of fibre reinforced lightweight concrete with composition of various fibres and nature of fibres.For this purpose hybrid of hooked steel fibres of length 50mm and chopped glass fibres used for polymer products. This study results in the optimisation of fibres and lightweight aggregates with comparison of the concrete specimen strength at 7and 28 days with improved specific properties of FRC compositesshowing the compressive strength, ,flexural strength,split tensile strengthof the specimen.