Title: Improving Column Confinement; Part 1: Assessment of design provisions

Author(s): K.J. Elwood, J. Maffei, K.A. Riederer, and K. Telleen

Publication: Concrete International

Volume: 31

Issue: 11

Appears on pages(s): 32-39

Keywords: transverse reinforcement, confining pressure, axial load, drift ratio

DOI:

Date: 11/1/2009

Abstract:
Column confinement provisions in ACI 318-08 are discussed and compared with provisions in other building codes as well as provisions proposed by other researchers. Key parameters include axial load, unconfined cover concrete, and amount and spacing of longitudinal reinforcement. The confinement provisions are evaluated using data from tests of rectangular columns. Drift capacity as a function of confinement (relative to that suggested by a specific confinement equation) show that the provisions in ACI 318-08 are less conservative than provisions published in the Canadian and New Zealand building codes.