This study examines the use of 15 different intensity measures (IMs) for estimating structural collapse using results from incremental dynamic analysis (IDA). IDA results from 54 numerical models were considered, including (i) 12 reinforced concrete (RC) frame structures, (ii) 16 RC wall–frame structures and (iii) 26 steel buckling‐restrained braced frame structures. The height of the structures ranged from 2 to 20 storeys, with the initial fundamental period varying from 0.25 to 2.3 s. IMs were evaluated using two existing criteria: efficiency and sufficiency, along with their predictability and practicality. Among the 11 period‐independent IMs examined, peak ground velocity (PGV) and velocity spectrum intensity (VSI) were the best correlated with the intensity at collapse. For structures with an initial period shorter than 1 s, VSI was the most efficient of all IMs considered. For structures with periods longer than 1 s, the period‐dependent IMs—average spectral acceleration and filtered incremental velocity—were found to be the most efficient IMs. The efficiency of the IMs was observed to be relatively insensitive to the lateral load‐resisting system. In general, the period‐independent and period‐dependent IMs identified above exhibited comparable levels of sufficiency. Results indicate that velocity‐based IMs, such as PGV and VSI, performed well in terms of efficiency and sufficiency, particularly for short period structures. From a practical perspective, PGV and VSI offer advantages due to their efficiency, simplicity and period independence, making them suitable IMs for region‐wide or portfolio‐level assessments.
Pledger et al. (Sun,) studied this question.