Experimental Investigation of Deep Beams Containing High-Performance Fiber-Reinforced Cementitious Composite

High-performance fiber-reinforced cementitious composites (HPFRCCs) are a type of construction material consisting of cement mortar with fine aggregates and fibers. The unique feature of these materials is that under tensile load, unlike conventional concretes, they exhibit strain-hardening behavior. Therefore, evaluation of shear strength of these materials seems necessary. This study examined the effect of presence of different percentages of ribbed polymer fibers on the shear behavior of HPFRCC deep beams without stirrups and compared this effect with the role of stirrups. For this purpose, eight RC beams in two size groups were constructed, and then their shear strength and other parameters were measure and compared. The results showed that fibers can be used as partial replacement of the beam stirrups without any decline in shear strength, but also to achieve improved shear ductility and resistance to shear crack nucleation. However, stirrups also played an effective role in delaying the nucleation of the first shear cracks.