SEISMIC ASSESSMENT OF A PRE-1970S REINFORCED CONCRETE FRAME BUILDING WITH PLAIN ROUND REINFORCING BARS

摘要

Seismic performance of an existing reinforced concrete frame building constructed in New Zealand in the late 1950s was assessed by conducting non-linear static and non-linear dynamic analysis. The non-linear behaviour of individual reinforced concrete members was based on the simulated seismic loading tests conducted on asbuilt reinforced concrete beam-column joint units, which represented the subject building and contained plain round reinforcing bars.Both non-linear static push-over and non-linear dynamic analyses showed that the overall non-linear performance of the building was mainly dominated by the non-linear behaviour of the beams. The building would not develop a collapse mechanism prior to the attainment of the maximum local deformation capacity,and no ductility can be relied on. Comparison with the results for deformed longitudinal reinforcing case shows that the current seismic assessment procedure could significantly overestimate the building capacity if plain round longitudinal bars were actually present instead.