Abstract
The work described in this paper deals with the assessment of the duration characteristics for horizontal and vertical components of strong ground motion records obtained in Japan, U. S., Mexico and Greece. The accelerograms used correspond to a range of earthquake magnitudes, between 5.1 and 8.1, to distances to the fault between 0.08 and 484km and to local subsurface conditions ranging from rock to soft clay. A total of 326 horizontal and 116 vertical components were used in the study. The definition of the strong motion duration in this study is closely related to the part that contributes significantly to the seismic energy. The duration characteristics of the above-mentioned strong motion records, using the proposed definition have been estimated and compared with their corresponding values as given by Trifunac-Brady and McCann-Shah. Correlations have been established between strong motion duration obtained by various definitions and magnitude, distance to the fault and local subsurface conditions.
