Rating of Indian ground motion records

A nonlinear dynamic analysis method in earthquake-resistant design requires real-time ground motion records. However, a definite criterion is required for ground motion selection. In the present study, a damage potential measure ‘distance from zero-amplitude axis (dZ-A)’ is developed through multivariate analysis of 21 different ground motion parameters for ground motion rating. These 21 parameters include peak ground acceleration, peak ground velocity, arias intensity, acceleration spectrum intensity, significant duration, predominant period, etc. along with moment magnitude, site class and hypocentral distance. The analysis is carried out in an orthogonal principal component space, using 433 Indian ground motions, recorded over magnitudes of Mw 4.5–7.2. Further, the goodness of dZ-A is validated through comparison with MMI values.