Journal Papers

Qiu, Jianlei

Gong, JX (reprint author), Dalian Univ Technol, Sch Civil Engn, Dalian, Peoples R China.

Gong, Jinxin,Zhang, Qin,Feng, Zhibin

2019-09-01

PROCEEDINGS OF THE INSTITUTION OF CIVIL ENGINEERS-STRUCTURES AND BUILDINGS

SCIE、EI

J

172

9

632-648

0965-0911

models (physical); seismic engineering; strength & testing of materials

Buckling of longitudinal bars is a common failure mode in reinforced concrete columns under earthquake, and can lead to the deterioration of structural seismic performance. In this study, a numerical method for predicting the average behaviour of reinforcing bars in compression considering the influences of buckling is developed. The bare reinforcing bar is divided into several segments, and a set of differential equations is established, in which both the material and geometrical non-linearities are taken into account. Then, a set of non-linear equations is derived by solving these differential equations and combining the conditions of geometrical compatibility and mechanical equilibrium so that the uniaxial compression stress-strain relations of buckling bars can be calculated numerically. The developed numerical method is verified against experimental data. The results of simulation and test are analysed; it is found that, unlike the case of elastic buckling, buckling of the reinforcing bars with commonly used bar length-to-diameter ratio usually occurs in the post-yield stage, and the degradation of post-buckling stress is mainly affected by the bar length-to-diameter ratio, the yield strength and the ultimate strength-to-yield strength ratio. Finally, a pseudo-material stress-strain relationship of a reinforcing bar in compression considering the effects of buckling is established by performing parametric analysis.