SUGGESTED EQUATIONS FOR MECHANICAL PROPERTIES OF SELF COMPACTING CONCRETE STRENGTHENED WITH STEEL FIBERS AND EFFECT OF SUCH FIBERS ON SHEAR CAPACITY OF SIMPLY SUPPORTED DEEP BEAMS UNDER AXIAL LOADS

Abstract

Deep beams are structural elements that are commonly designed for bridges, girders, foundation walls, pile caps, and others. Also, using Self Compacting Concrete (SCC) mix for the deep beams is a suitable choice for deep beams because of reinforcement congestion therein. The main objective of this work is to study the shear capacity of SCC reinforced concrete deep beams subjected to axial load so that both experimental and analytical works are done. The experimental work consists of four simply supported deep beams cast by using SCC mix with steel fibers and tested. All these beams have dimensions 1300mm length, 350mm high, 150mm width and have been subjected to axial force with (100) kN value and then subjected to two-point loads. The variables of this work are vertical and horizontal shear reinforcement and steel fibers ratio in order to study their effects on first crack load and ultimate load and mid span deflection. From the experimental results obtained all the tested beams failed by diagonal splitting mode with some crushing at support zones (in some beams). The second part is the analytical study of this research, including presents, proposed equations to estimate the mechanical properties like compressive strength f`cf, splitting tensile strength ftf, modulus of rapture frf, and modulus of elasticity Ecf of fibrous SCC.