A Study on Shear Performance of Longitudinally Reinforced SFRC Beams with Satisfactory Composite-Recycled Aggregates

Composed of recycled small-particle coarse aggregates with virgin large-particle crushed stones, satisfactory composite-recycled aggregates are developed to overcome the shortcomings of large particle recycled coarse aggregate, making a new concrete with similar mechanical properties to conventional concrete. This brings a development of steel fiber reinforced satisfactory composite-recycled aggregate concrete (SFRSCAC) used for structural engineering. To identify the shear performance of longitudinally reinforced SFRSCAC beams without stirrups, ten test beams were fabricated and experimentally studied by four-point bending tests, incorporating ingot-mill steel fiber in volume fraction from 0 to 2.0%. Results show that steel fibers could delay shear cracking and effectively increase shear strength of test beams, but could not fundamentally change the shear failure with brittle characterization of bond cracking along the longitudinal reinforcement. The assessment using existing prediction formulas of reinforced steel fiber reinforced concrete (SFRC) beams demonstrates that the shear cracking resistance and shear strength of longitudinally reinforced SFRSCAC beams reach the level of reinforced SFRC beams. This provides a basis for broadening the application of SFRSCAC, just like conventional SFRC in structural engineering.