Скачать или смотреть Effect of Tensile Strain Capacity of UHPC on the Bond with Steel Reinforcement

Presented By: Amr Soliman, SUNY University of Buffalo

Description: In reinforced concrete structures, the bond of the steel reinforcement is usually governed by the cracking of the surrounding concrete leading to brittle splitting failure. The bridging effect of fibers in Ultra-High-Performance Concrete (UHPC) results in high tensile strength, leading to significantly higher bond strength of steel reinforcement. Furthermore, Strain Hardening Ultra-High-Performance Concrete (SH-UHPC) possesses high tensile strain capacity up to 6% in addition to high tensile strength. Therefore, an SH-UHPC could provide more efficient containment of the steel reinforcement and improve the bond behavior. This study evaluates the effect of strain capacity of concrete on the bond performance by comparing UHPC and SH-UHPC specimens. Double-rebar pullout specimens are made from the two materials, with varying cover thickness and embedment length. It was found that higher tensile strength of concrete led to greater bond strength. On the other hand, higher strain capacity of concrete resulted in a more ductile behavior and greater energy dissipation.