Ductile cementitious composite with copper slag as fine aggregate

The invent of new construction materials and extensive research in concrete technology and cement chemistry has proved that, apart from proportioning concrete for high strength it is very important to design a concrete mix for ductile behaviour to be used in earthquake prone areas. The use of mineral and chemical admixtures in concrete has facilitated material scientists to invent special types of concrete to suit the current application. This research work is one such attempt in characterizing cement composite that is ductile and durable. Apart from using only Portland cement, mineral admixtures which are industrial by-products are used in this composite which makes this material a sustainable construction material. Concrete is a brittle material and this disadvantage in concrete was overcome by the addition of fibres in the matrix improving the flexural toughness of the material. Ductile Cementitious Composite (DCC) is different from the conventional fibre reinforced concrete (FRC) which is characterized by high tensile strain capacity and strain-hardening behaviour under uniaxial tensile loading. This property is accomplished by the fiber content, matrix proportion and the interface between the matrix and fibre. The formation of closely spaced multiple micro cracks in the matrix enables this composite to have the ductile behaviour. The self healing ability of these composites is another added advantage which enables the durability of the material. The autogenous healing of crack by the formation of additional calcite and CSH are responsible for the self healing capacity of these composites. The materials used for this composite is a blend of Portland cement, class F fly ash, silica fume, pulverized copper slag and PVA (Polyvinyl acetate) fibres. The concrete had a compressive strength of 64 to 72 MPa and flexural strength of 4 to 6 MPa. Durability parameters were also studied to ascertain the permeability characteristics of concrete. (C) 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the 10th International Conference of Materials Processing and Characterization.