Parametric Investigations on Columns with Un-Bonded Reinforcing Bars for Damage Control

• Published in: Advances in structural engineering 2007-04, Vol.10 (2), p.171-181
• Main Authors: Chen, G., Fukuyama, H., Teshigawara, M., Etoh, H.
• Format: Article
• Language: English
• ISSN: 1369-4332; 2048-4011
• DOI: 10.1260/136943307780429707

Influential factors on concrete cracking in column ends are studied by a non-linear finite element model. Following the previous strategy developed in the Building Research Institute in Japan, un-bonded zones are introduced into column ends and additional re-bars added around the un-bonded zones. The parametric studies of the length of the un-bonded zone and the amount of the additional re-bars are conducted. The load-displacement curves and cracking patterns in concrete are obtained and compared for all of the considered designs. The parametric studies show that the length of the un-bonded zone has significant influences on concrete cracking in column ends; the longer the un-bonded zone is, the better the concrete cracking is controlled in column ends. The studies also show that the additional re-bars slightly influence the load-displacement curves and cracking patterns. The influences of the bond-slip on the numerical analysis are also investigated and the proper parameters of the bond-slip are determined and recommended by the parametric studies.