Static pushover versus dynamic collapse analysis of RC buildings

Owing to the simplicity of inelastic static pushover analysis compared to inelastic dynamic analysis, the study of this technique has been the subject of many investigations in recent years. In this paper, the validity and the applicability of this technique are assessed by comparison with 'dynamic pushover' idealised envelopes obtained from incremental dynamic collapse analysis. This is undertaken using natural and artificial earthquake records imposed on 12 RC buildings of different characteristics. This involves successive scaling and application of each accelerogram followed by assessment of the maximum response, up to the achievement of the structural collapse. The results of over one hundred inelastic dynamic analyses using a detailed 2D modelling approach for each of the twelve RC buildings have been utilised to develop the dynamic pushover envelopes and compare these with the static pushover results with different load patterns. Good correlation is obtained between the calculated idealised envelopes of the dynamic analyses and static pushover results for a defined class of structure. Where discrepancies were observed, extensive investigations based on Fourier amplitude analysis of the response were undertaken and conservative assumptions were recommended.