Structural Performance of Reinforced Concrete Beams with Various Cross-Section

Abstract

The deflection of reinforced concrete beams with various cross-sections was investigated in this work. The experimental program comprised of four reinforced concrete beams that were simply supported. They were put through a two-point load test. High to width ratio (h/b) was (0.36, 0.64, 1, and1.56), concrete compressive strength was from 27 MPa. The gradual increase in the (h/b) ratio (from 0.36 to 0.64, 1 and 1.56) with (27 MPa) compressive strength of concrete leads to increase the first crack load for the (N2, N3 and N4) by (74%, 111% and 122%) respectively as compared with (N1), the beams (N2, N3 and N4) exhibits an increase in the yielding load by (41.2%, 70.6% and 64.7%) respectively as compared with (N1), increase the ultimate load by (25% - 130%). The ductility index is reduced with gradual increase in the (h/b) ratio (from 0.36 to 0.64, 1 and 1.56) for (27 MPa) concrete compressive strength by (1.2% - 25.5%). For the beams (N1, N2, N3 and N4) it is noticed that the central deflection of the four beams reduced gradually at the same load with increase in the (h/b) ratio from (0.36 to 0.64, 1 and 1.56) with constant (27 MPa) compressive strength concrete. The maximum crack width decreases gradually with gradual increase in the (h/b) ratio (from 0.36 to 0.64, 1 and 1.56) for constant (27 MPa).

Keywords

• Deflection,
• Cross-sections,
• High to width ratio (h/b),
• Ductility index