Investigation of Shear Behavior of Hybrid High Performance Fiber Reinforced Cementitious Composites (HybHPFRCC): A Novel Approach

The concept of integrating fibers into cement-based materials reduces the brittleness of concrete, imparting a high tensile capacity, compressive strength, and shear capacity. Hybridization of fibers has been a subject of considerable interest among researchers. This process involves combining different fibers, considering various characteristics such as aspect ratio, material, diameter, length, modulus of elasticity, and tensile strength. Several researchers have explored the characteristics of cement-based composites by utilizing mono-fiber reinforced composites in tension and compression. However, there remains a dearth of studies on the response of composites under shear incorporating hybridization of Polypropylene (low modulus) and steel (high modulus) fibers. Total Fiber dosage has been kept at 1%, 1.5%, and 2% by weight of cement in a composite. A uniaxial Compression test was conducted for all these compositions, and it was observed that 25% to 30% compressive strength was enhanced. For the shear test, a novel method is employed to characterize the shear behavior of a hybrid high-performance fiber-reinforced cement-based composite. The shear test method is based on the establishment of elements of zero restraints. The applied compressive stresses are transformed into plane shear stresses within the prescribed area. It has been concluded that the coupling effect of fiber raises the shear strength 2 to 2.5 times the control samples. An effort has been made to correlate the findings of this shear test method with the shear equation specified by ACI.