Cyclic behaviour of lightly-reinforced concrete columns with short lap splices subjected to unidirectional and bidirectional loadings

Abstract

Reinforced concrete (RC) buildings constructed prior to the 1970s could be vulnerable to earthquakes due to inadequate reinforcement details such as widely spaced transverse reinforcement and short lap splices. Most of these buildings were designed without considering seismic loads. The objective of this study was to investigate the cyclic behaviour of the lightly reinforced concrete columns with short lap splices in older RC buildings under unidirectional and bidirectional loadings. Experimental tests were conducted using four full-scale specimens. The estimates of modelling parameters and lateral strength obtained from the measured cyclic curves of the specimens were compared with the values calculated according to ASCE 41-17. Cyclic behaviour of lightly reinforced columns with short lap splices was significantly affected by loading types and the levels of axial load. The modelling parameters and lateral strength were also affected by the levels of axial load and by loading types (unidirectional and bidirectional) deviating from the constant values specified in ASCE 41-17 for these parameters.