Flexural ductility of high-strength concrete columns with minimal confinement

Deformability evaluation of high-strength reinforced concrete columns

“…It has been verified by theoretical analyses (Bai and Au, 2009;Kim et al, 2007;Lam et al, 2009;Pam and Ho, 2001) and experimental tests (Ahn and Shin, 2007;Bayrak and Sheikh, 1998;Ho and Pam, 2003a;2003b;Hong et al, 2006;Li et al, 1991;Sharma et al, 2007;Watson and Park, 1994;Xiao et al, 2008;Youssef and Rahman, 2007) that the flexural strength and ductility performance of reinforced concrete (RC) columns, including high-strength RC (HSRC) columns, can be improved significantly by installing a sufficient amount of transverse reinforcement to confine their concrete core. The transverse reinforcement not only averts brittle failure owing to shear, but also confines the core area to avoid premature concrete crushing and postpone inelastic buckling of longitudinal steel effectively.…”

“…In the past, numerous researchers have conducted cyclic reversed loading tests on RC columns to assess their seismic performance by displacement ductility factor (Ahn and Shin, 2007;Baczkowski and Kuang, 2008;Xiao et al, 2008;Youm et al, 2007) or displacement as well as curvature ductility factor (Bayrak and Sheikh, 1998;Ho and Pam, 2003a;2003b;Li et al, 1991;Watson and Park, 1994) which is the ratio of the ultimate to the yield value of the respective parameter. Some theoretical analyses were also carried out to investigate the flexural ductility of RC beams and columns (Bai et al, 2007;Bai and Au, 2009;Ho et al, 2003;Kwan et al, 2002;Lam et al, 2009;Su et al, 2006;. In addition to ultimate curvature and ultimate displacement, ultimate rotation of the member is also important in the design of earthquakeresistant structures.…”

“…Both ultimate displacement and ultimate rotation are used in this study to measure the deformability (deflection and rotation) of HSRC columns. Without knowing the deformability of a member, the redistribution of internal forces after the formation of plastic hinges during an earthquake attack cannot be predicted and the member would fail in a brittle manner (Inel et al, 2007;Lam et al, 2009;Spence, 2008;Wu et al, 2004).…”

“…Both ultimate displacement and ultimate rotation are used in this study to measure the deformability (deflection and rotation) of HSRC columns. Without knowing the deformability of a member, the redistribution of internal forces after the formation of plastic hinges during an earthquake attack cannot be predicted and the member would fail in a brittle manner (Inel et al, 2007;Lam et al, 2009;Spence, 2008;Wu et al, 2004).Very limited information is available on the deformability design of normal-strength RC (NSRC) and highstrength reinforced concrete (HSRC) columns because of the complicated behaviour of plastic hinges in RC structures (Bae and Bayrak, 2008;Bayrak and Sheikh, 2001;Daniell et al, 2008;Haskett et al, 2009;Inel and Ozmen, 2006;Jaafar, 2008;Morley, 2008). Previous experimental studies on NSRC and HSRC columns focused mainly on the flexural ductility performance (Ahn and Shin, 2007;Bayrak and Sheikh, 1998;Li et al, 1991;Watson and Park, 1994).…”

Estudio Experimental Y Numérico De La Capacidad De Deformación De Soportes Esbeltos De Hormigón Armado

“…Otros modelos simplificados con menor trascendencia han sido propuestos para el cálculo de la deriva última, como el de Lam et al (2003) [75]. Este modelo presenta una limitada aplicación, ya que sólo es válido para elementos de hormigón con esbelteces inferiores a 3, de hormigón convencional, y bajos niveles de carga axial.…”