2.4 Hwang et al. (2004)

1)      Reference

Howard Hwang, Chih-Kun Lin and Yeong-Tein Yeh, 2004, Derivation of Attenuation Relations of Arias Intensity Using the Chi-Chi Earthquake Data, 13th World Conference on Earthquake Engineering Vancouver, B.C., Canada, August 1-6, Paper No. 3108.

 

2)      Used strong motion data

- Area: Taiwan

- Period: 1999 Chi-Chi Taiwan earthquake

- Number of events: 4

main shock 1999/09/20 Mw7.7

              after shock 1999/09/20 Mw6.2, 1999/09/22 Mw6.4, 1999/09/25 Mw6.5

 

3)      Definition of intensity

Arias[1] intensity

 

4)      Definition of distance

Source distance

 

5)      Applicability written in this paper

Rupture of a thrust fault for sites in the footwall area or in the area from the fault

 

6)      Empirical attenuation formula

              Ih: Arias intensity (m/s)

              Mw: moment magnitude

              r: source distance (km)

              ε: random error

              IEW: Arias intensity in the east-west direction

              aET(t): acceleration time history in the east-west direction

              t0: total duration of ground motion

              R: shortest horizontal distance form a station to the surface projection of a fault (km)

              h: focal depth (km)

 

 

Table 2.4-1 Regression results from two-step regression analysis method

 

 

 

 

 

 

 

 

 

 

 


[1] Arias, A. “A measure of earthquake intensity.” Hansen RJ, Editor. Seismic Design for Nuclear Power Plants.

Cambridge: The M.I.T.Press, 1970: 438-489.