Numerical Assessment on Continuous Reinforced Normal-Strength Concrete and High-Strength Concrete Beams

Abstract

High-strength concrete (HSC) has been broadly applied to various civil structures for its advantages including high compressive strength and excellent durability and creep resistance. However, the brittleness of HSC raises concern about its use in practice. So far study on continuous reinforced HSC beams is limited. This work investigates the structural response of reinforced HSC continuous beams, and the results are compared with those of the counterparts made of normal-strength concrete (NSC). By applying a finite element method verified by experimental data, a comprehensive assessment is performed on two-span reinforced NSC and HSC (compressive strengths of 30, 60 and 90 MPa) continuous beams. A wide range of flexural reinforcement ratios are used to cover both under-reinforced and over-reinforced beams. The results show that reinforced HSC beams exhibit better flexural performance in terms of ultimate load, deformation, flexural ductility and moment redistribution, when compared to reinforced NSC beams. Formulae relating flexural ductility and moment redistribution with either neutral axis depth or tensile steel strain are suggested.