Pushover Analysis: Proposals for Modification

Estimating earthquake-induced response, both in elastic and post-elastic range, with adequate precision is a major challenge to performance-based seismic design. A simple effective method known as pushover analysis amenable to be exercised in routine design is gaining popularity in the recent times. This emerging methodology, though appears to be promising, is observed to be deficient. It is this backdrop that compels to review such methodology closely to frame certain proposals for better performance of the same. Such proposals are made, on the one hand, through adjusting the response reduction factor (R) to address the effect of degrading hysteresis behaviour under cyclic loading in Procedure A, B, C of Applied Technology Council-40 (ATC-40), while, on the other for Displacement coefficient method, the displacement demand is suggested to be magnified by R and R/2 for degrading and non-degrading systems, respectively. Efficacy of the proposals is checked through representative case studies.