FAILURE MODE AND STRENGTH CHARACTERISTICS OF NON-GRADED COARSE AGGREGATE CONCRETE BEAMS

This paper is devoted to investigate experimentally the variation of mechanical properties of concrete as a result of using one grade of crushed and rounded gravels gradient in conventional concrete mix instead of well graded gravel, in addition to its effect on structural behavior of reinforced concrete beams. The experimental work includes investigation of 30 cube, 30 cylinder and 30 prisms specimens to evaluate compressive strength, modulus of elasticity and modulus of rupture for concrete. While the structural behavior of reinforced concrete beams has been studied through casting and testing of ten (180 *200 * 1100) mm beam specimens. This work concluded that the failure mode has been changed from flexural to shear failure, failure and cracking loads was also affected adversely by using one gradient of gravel and the ductility and stiffness are decreased when using one gradient of gravel instead of well graded gravel.