STRESS - STRAIN RELATIONSHIPS FOR CONFINED CONCRETE: RECTANGULAR SECTIONS

Abstract

An experimental investigation into the behaviour of square, confined, reinforced concrete columns was undertaken. Thirty 450 mm square, 1200 mm high units were cast with varying amounts of longitudinal and lateral steel. These were subjected to concentric or eccentric axial loads to failure at slow or dynamic loading rates. Confinement requirements of reinforced concrete columns are discussed and the results and analyses of experimental work presented. Results include an assessment of the significance of loading rate, eccentricity, amount and distribution of longitudinal steel, and the amount of confining steel. A general stress-strain curve for rectangular concrete sections loaded at seismic rates is proposed and compared with existing curves based on previous static loading tests.