Pullout Resistance of Reinforcing Bars Embedded in Hardened Concrete.

摘要

Holes for embedding reinforcing bars were diamond-drilled into mass concrete test blocks. The holes were 1in. (25.4mm) in diameter and deep enough to embed No. 4and No. 6deformed reinforcing bars to depths of 5, 8, 10,and 20nominal bar diameters. Portland-cement grouts and commercially available epoxy-resin systems were used to anchor the bars in the drilled holes. Bonding agents were allowed to cure,and the reinforcing bars were axially loaded to determine which bonding agent offered the most pullout resistance. In all instances,the epoxy-anchored reinforcing bars exhibited more resistance to pullout than did the bars anchored with the cement grouts. The bonding agents evaluated in this investigation are recommended for anchoring reinforcing bars in drilled holes in hardened mass concrete;however,certain limitations are specified for their use. (Author)