A case study on pre 1970s constructed concrete exterior beam-column joints

Abstract

AbstractThe exterior beam-column (EBC) joints in the second generation concrete structures (built prior to 1970s) were observed to underperform during earthquakes mainly due to the lack of shear reinforcement and improper construction practices. In this paper, results of a detailed parametric study conducted using 3D finite element analysis are presented to illustrate the performance of three types of substandard EBC joints that are typical to pre 1970s construction practices designed according to: (1) ACI 318-1971, (2) old Japanese practice and (3) old Indian practice. In addition, the influence of concrete strength, beam and column flexural reinforcements on the load carrying capacity of substandard EBC joints are investigated. The substandard joints analyzed in this study failed in a brittle fashion due to the shear failure of joint core concrete and anchorage slippage