Plastic Hinge Rotation Capacity of Reinforced HPFRCC Beams

Abstract

High performance fiber reinforced cementitious composite (HPFRCC) materials exhibit strain hardening behavior under tensile loading. This strain hardening response occurs after the first cracking of the material. In this paper, experimental and parametric studies were conducted to assess the influence of the compressive strength, loading type, and tension reinforcement ratio (ρ) on the ultimate deformation characteristics of reinforced HPFRCC beams. The analytical and numerical results for simply supported beams with different amounts of tension reinforcement ratios under three different loading conditions are presented and compared with each other and with the available experimental data. The plastic hinge rotation capacity increases as the loading condition changes from the concentrated load in the middle to the uniform load, and it reaches a maximum in the case of two-point loading. The effect of loading type on the plastic hinge rotation capacity of the reinforced beams with a high amount of ρ is not as significant as that of lightly reinforced beams. Based on the analytical results, new simple equations as a function of the tension reinforcement ratio and the loading type are proposed. Analytical results indicate that the proposed equations can be used with sufficient accuracy to calculate the plastic hinge rotation capacity of reinforced HPFRCC beams.