NEHRP Clearinghouse

Title
Alaskan Earthquake (1964) Tall Building Damage Review, Optimum Seismic Protection for New Building Construction in Eastern Metropolitan Areas.
File
PB80116395.pdf
Author(s)
Whitman, R. V.; Vanmarcke, E. H.; Reed, J. W.; Kausel, E. B.
Source
National Science Foundation, Washington, DC. Engineering and Applied Science., July 1972, 11 p.
Identifying Number(s)
INTERNAL STUDY-11
Abstract
This review organizes and presents information on building performance in terms of damage probabilities. These probabilities are the elements of matrices which quantify the uncertain relationship between the amount of building damage and the intensity of ground shaking. They are a basic component of the input to an analysis aimed at predicting losses of life and property during future earthquakes. The peak acceleration of the 1964 Alaskan earthquake is estimated at about 0.16g and the damaging shaking lasted for about three minutes. The Modified Mercalli Intensity was about 1X to X. Wood frame dwellings and other low rise buildings not located in landslide areas performed very well. All buildings of five or more stories in the Anchorage area suffered some structural damage. The predominant period of the horizontal ground motion in Anchorage was estimated at 0.5 seconds or longer. Most of the buildings had reinforced concrete shear walls as their principal lateral force resisting system. Almost all of the structures built since 1955 were constructed according to the UBC seismic zone three, and those built before 1955 had roughly a zone two strength. A summary of the number of buildings by height and zone used in developing the damage probability matrices is presented.
Keywords
Ground motion; Buildings; Damage assessment; Earthquake engineering; Earthquake resistant structures; Seismic design; Earthquakes; Anchorage (Alaska); Probability theory; Earth movements; Alaska; Tall buildings