Title: High-Strength Reinforcement in Columns under High Shear Stresses

Author(s): Drit Sokoli and Wassim M. Ghannoum

Publication: 318Reference

Volume:

Issue:

Appears on pages(s): 605-614

Keywords: columns; high-strength steel; reinforced concrete; seismic

DOI:

Date: 5/1/2016

Abstract:
This study investigated the performance of seismically detailed concrete columns reinforced with high-strength steel. Columns were subjected to high shear stresses and relatively high axial load to investigate the ability of high-strength reinforcement in maintaining the integrity of concrete shear-transfer mechanisms. Two columns (CS60 and CS80) were respectively reinforced with conventional Grade 60 (420 MPa) and Grade 80 (550 MPa) ASTM A706 bars. A third column, CS100, was reinforced with newly developed Grade 100 (690 MPa) bars. Columns had almost identical reinforcement layouts and flexural strengths. Shear and axial failure occurred at comparable drift levels in CS60 and CS80. CS100 sustained bond degradation around the longitudinal bars at relatively low drifts, raising questions about bar development lengths and allowable lengths of concrete members reinforced with high strength steel. Strain demands in longitudinal and transverse bars were significantly higher in the specimens reinforced with high strength steel.