Title: Local Bond of Deformed Bars With Different Diameters in Confined Concrete

Author(s): Parviz Soroushian and Ki-Bong Choi

Publication: Structural Journal

Volume: 86

Issue: 2

Appears on pages(s): 217-222

Keywords: bond (concrete to reinforcement); bond stress; confined concrete; cyclic loads; deformed reinforcement; earthquakes; joints (junctions); models; slippage; tests; Structural Research

DOI: 10.14359/2731

Date: 3/1/1989

Abstract:
Slippage of the beam reinforcement crossing the interior joints in reinforced concrete frames can lead to large fixed-end rotations and overall beam deformations, causing major structural damage under severe seismic excitations. It is thus important to anchor adequately deformed bars inside the confined core of earthquake-resistant joints. The key factor governing the anchored-bar behavior in confined concrete is the local bond stress-slip relationship. This investigation addresses the effects of bar diameter on this relationship. Experimental data have been generated on the local bond behavior for deformed bars of different diameters partially embedded in confined concrete. The results are used to assess the anchored bar-diameter effects on the ultimate local bond strength and local bond stress-slip relationship in confined concrete. Based on the test data, an empirical local bond constitutive model has been generated that accounts for the bar-diameter effects.