Flexural Capacity of Ultra High-Strength Concrete Beams with 150MPa

This study was performed to evaluate on the ductile capacities and flexural behaviors of 150MPa Ultra High strength concrete(UHSC) beam reinforced by SD400 and SD500 bars to maximum tensile steel ratio. The reinforced ultra-high-strength-concrete beam subjected to flexural moment behaves more brittleness than the moderate strength concrete beam reinforced with equal reinforcement ratio(��/��b, ��b=balanced steel ratio). In this study, 10 singly reinforced rectangular beam specimens used 150 MPa concrete compressive strength were tested to evaluate on flexural behavior. Test results are follows ; 1)The ductile capacity of RC beam with above 100MPa Ultra High strength concrete (UHSC) and without compressive steel significantly decrease as increase concrete strength and displacement ductility factor of 150MPa HSC indicates about 1.3~2.56. 2)when the concrete compressive strength with 150 MPa, the maximum reinforcement ratio should be used less than 0.625��b for ductile behavior