Torsional Ductility of Circular Concrete Bridge Columns

摘要

This research experimentally investigates the behavior of circular reinforced concrete columns under reversed cyclic torsion. The columns are reinforced using a new confinement technique which uses two opposing spirals (cross spirals) in order to enhance strength and ductility or to increase spiral spacing (pitch) to facilitate the passage of concrete during construction. Eighteen reduced scale R/C circular columns with four different length to depth ratios and several spiral spacings and patterns were built and tested. The columns were subjected to reversed cyclic twist to study the behavior of the new confinement technique. The torsional strength and ductility of these columns are compared to columns confined with a conventional single spiral reinforcement layout.