Shear Testing of Steel Fiber-Reinforced Lightweight Concrete Beams without Web Reinforcement

摘要

To investigate the effect of steel fibers on the shear strength of lightweight concrete beams without web reinforcement, a total of 12 beams were tested under four-point loads, including six steel fiber-reinforced lightweight concrete (SFRLC) beams and three normalweight steel fiber-reinforced concrete (SFRC) beams. The variables include the shear span-depth ratio (a/d) (2, 3, and 4), steel-fiber volume fraction (V_f = 0, 0.5, and 0.75%) and type of concrete (lightweight versus normalweight). The addition of steel fibers with V_f of 0.75% was found to increase the shear capacity by 30% and promote a ductility of 5.3 or higher. The test results also indicate that the a/d adversely affects the shear capacity. Models for SFRC beam shear strength were reexamined using the current and prior test data to assess the shear strength of the SFRLC beams. Finally, a design shear strength equation for SFRLC beams without web reinforcement has been proposed based on the review.