NEHRP Clearinghouse

Title
Strong-Motion Duration of Earthquakes.
File
PB272001.pdf
Author(s)
Vanmarcke, E. H.; Lai, S. S. P.
Source
National Science Foundation, Washington, D.C. Div. of Advanced Environmental Research and Technology., July 1977, 38 p.
Identifying Number(s)
R77-16
Abstract
A simple procedure is proposed to estimate the strong-motion duration of earthquake motions. The proposed strong-motion duration is nearly proportional to the quantity (I sub o)/(a(max)squared), in which a(max) is the maximum ground acceleration and I sub o is the integral of the squared accelerations. The proportionality factor is weakly dependent on the predominant period of the ground motion. The procedure has been applied to 140 horizontal components of strong earthquake ground motions. The results are tabulated and summarized in the form of histograms. The dependence of strong-motion duration on earthquake magnitude and epicentral distance is also examined.
Keywords
Seismic waves; Earth movements; Seismic epicenter; Time measurement; Buildings; Earthquake engineering; Ground motion; Acceleration (Physics); Earthquakes