MECHANICAL PROPERTIES OF HYBRID FIBRE REINFORCED CONCRETE

Abstract

This paper contains the behavior of Hybrid Fiber reinforced concrete with the partial replacement of
natural coarse aggregate with recycled coarse aggregate and cement with fly ash. Application of recycled materials in
the building industry is essential for permanently sustainable development. Concrete is good in compression and weak
in tension. Low tensile strength and the poor resistance to cracking of the concrete lead to severe effect in its
properties. Introduction of fibers into concrete will increase its tensile strength and resistance to cracking.
Polypropylene fiber and glass fibers are chemically inorganic. Because of increase in coal based thermal power plants
there is an increment in the production of fly ash which is a waste material. If fly ash is not disposed properly it will
be hazardous. As a solution it is used in the concrete as a partial replacement of cement. This replacement reduces the
environmental pollution and improves the mechanical properties of concrete. This paper is focused on the
experimental program aimed at verifying selected material properties of Hybrid fiber reinforced concrete in which all
of the natural coarse aggregates are partially replaced by recycled aggregates and cement is partially replaced by fly
ash. The combination of recycled waste, fibers and binder creates an unusual fiber reinforced concrete which is a new
composite. In this study the percentages of recycled aggregate (25%), fly ash (20%) and polypropylene fibers (0.6%)
are fixed as per previous literatures. And with this combination, different percentages (0%, 0.2%, 0.4%, 0.6%, 0.8%
and 1.0%) of glass fibers are used to know the mechanical properties like compressive strength, split tensile strength
and flexural strength of the Hybrid fibre reinforced concrete. The optimum dosage of the glass fibres with 0.6%
polypropylene fibres is found at 0.6%.