A Cursory Study of Behavior of Three Instrumented Buildings During the Recent M7.0 Anchorage, AK, Earthquake of November 30, 2018

Date: 4/26/2019

Time: 06:00 PM

Room: Grand Ballroom

This is a study of the recorded responses of three buildings instrumented by the U.S. Geological Survey (USGS) in Anchorage, AK during the M7.0 Anchorage, AK earthquake of November 30, 2018 (8:29:28 AKST, epicentral coordinates:  61.340N 149.937W, depth 40.9 km) [www.strongmotioncenter.org, last accessed December 18, 2018]. The earthquake caused  strong shaking in Anchorage since the well-known 1964 M9.2 earthquake. The three buildings are identified by the number of stories they have (see Table 1). Essential dynamic characteristics of each building and significant behavioral aspects, such as beating and torsional motions are identified. In Table 1, recorded peak accelerations, displacements, and average drift ratios computed using the peak displacements at the roof levels are provided. These average drift ratios imply that the motions are at levels expected not to cause damage to the buildings. Visualization videos of both the 14-story and 20-story buildings are depict overall shaking of the buildings during the earthquake.

Table 1: Number of stories, heights, peak accelerations and displacements, average drift ratios  [H=Height, GRPA=Ground peak, RP=Roof peak, a=acceleration(g), d=displacement (cm), ADR=Average Drift Ratio, f=fundamental freq.(Hz)]

Building                       H (m)       GRP           RP            ADR                     f

                                                      a            a      d           (%)                     (Hz)                               

14-story (Frontier)        51.5      0.19      0.22    23.8       0.3       0.45(NS)   0.35(EW)

20-story (Atwood)        80.5      0.21      0.44    30.0       0.4       0.44(NS)   0.37(EW)

22-story (Hilton)          74.0       0.21     0.65     21.8      0.35      0.41(NS    0.41(EW)

Presenting Author: Mehmet Celebi

Authors