Joint Symposium of Seismic Hazard Assessment
June 17-21, 2013, Sendai, Japan

Empirical Site Correction for Ground
Motion Simulation
Kuo-Liang Wen1,2, Jyun-Yan Huang1,and Chun-Te Chen1
1. Department of Earth Sciences, National
Central University, Taiwan, R.O.C.
2. NCREE, NARL, Taiwan, R.O.C.

1

OUTLINE
Introduction
Data and Method
Empirical Site Effects
Ground Motion Simulation
Discussions and Conclusions22

3

Locations of the strong
motion stations in Taipei
area. Numbers indicate
the station codes ofTSMIP network (CWB).

4Basement +SunShang
Formation

566•Stocastic Method•SMSIM (Boore, 2009) : point source•EXSIM (Motazedian and Atkinson 2005;
Assatourians and Atkinson 2007; Boore 2009):

finite faultstation

7fault1991 ~ 2009
Mag. < 6
Dep. < 40 km
203 earthquakes
4 target events8 Empirical Site Correction

SOBS-S

Soil

RockVery Hard Rock
(ENA-A, AB06)
Simulation ofearthquake
half space9 Empirical Site Correction

SSIM-R

Soil

RockVery Hard Rock(ENA-A, AB06)
Simulation ofhalf space

10earthquake

Parameters for SMSIM:(Sokolov et al., 2009)
Shear-wave
velocity (VS)

3.6 km/s

Density (ρ)

2.8gm/cm3

Geometric
spreading Rb:b-1.0 (1–50 km)
0.0(50–170 km)-0.5(>170 km)(Sokolov 2000;Sokolov et al.
2000;Sokolov et al.
2001;Sokolov et al.
2003;Sokolov et al.
2006;Sokolov et al. 2009)

Quality factor

Zone ST: 80f0.9
Zone SO: 120f0.8
Zone DT: 60f1.0(Sokolov et al., 2006; 2009)κ (kappa)

0.05 sec.

Crustalamplification

ENA-A (Atkinson & Boore,2006)

11STSODT(Sokolov et al., 2006)

Parameters for SMSIM:(Sokolov et al., 2009)
MWStress(bar)12ML=1.961Mw+0.338+-0.256 , ML≦6.0
ML=5.115*(ln(Mw))-3.131±0.379 ,ML≧5.5(Cheng et al., 2010)
Window length:10.24 sec

Class B:
TAP086

TAP058

Vs30:942m/s

Vs30:1056m/s

Class C:TAP041

TAP057

Vs30:361m/s

13

Vs30:367m/s

TAP071
Vs30:831m/s

TAP089
Vs30:442m/s

Class D:
TAP003

Vs30:209m/s

Class E:
TAP001
Vs30:160m/s

14TAP017

TAP090

Vs30:221m/s

Vs30:325m/s

TAP005

TAP096

Vs30:177m/s

Vs30:161m/s

150.52.015

Dominant frequency
SMSIM

Microtremor

16(redraw of Wen and Huang, 2012)

Amplification of 0.5 HzSMSIM

Microtremor

17(redraw of Huang, 2009)

Amplification of 2.0 Hz
SMSIM

Microtremor

18(redraw of Huang, 2009)

Spectral ratio contours of the Chi-Chi aftershocks in the Taipei basin.
19

Sungshan Formation Bottom--- Taipei Basin20

2011.1修訂後公告之臺北盆地
修訂後公告之臺北盆地
設計地震微分區圖Microzonation Map of Taipei
Basin in the Building Code
Modified on 2011.

TAP024FASo
DSPD = ∑i =0.2  log10× df FAS s10

Residual = lnPGAo-lnPGAs

σ ln Err =1N2()
Re
sidual∑ii =1Nr = Correlation Coefficient
21

Yatt=0.00369e1.75377M[R+0.12220e0.78315M]-2.05644
σlnErr = 0.78

22

2003_0609 Mw5.6 dep23.22 km
TAP002
TAP052
TAP080Class C:23

2003_0609 Mw5.6 dep23.22 km
TAP009TAP015
TAP017

Class D:24

2003_0609 Mw5.6 dep23.22 km
TAP001
TAP021
TAP091

Class E:25

2003_0609 Mw5.6 dep23.22 km

26

σlnErr:0.863 → 0.431
1.325→0.336
Avg DSPD: 0.419 → 0.345Avg r: 0.564 → 0.805

Observation

Site correction ofSMSIM

27

Attenuation
Equation

Residual:ln(OBS/SMSIM)

2000_0910 Mw6.19 dep17 km
1995_0324 Mw5.5 dep76 km

σlnErr:0.717 → 0.487
1.458 → 0.456
Avg DSPD: 0.629 → 0.559
Avg r: 0.430 → 0.66628

σlnErr:1.002 → 0.619
1.675 → 0.639
Avg DSPD: 0.473 → 0.418
Avg r: 0.560 → 0.669

Discussions and Conclusions•The stochastic point source model was used to obtain theempirical site transfer function for each soil site within theTaipei basin. (203 mag. < 6.0 and depth < 40 km)•Ground motion simulation can be performed for moderatemagnitude earthquakes by the stochastic point source
simulation to rock basement and added the empirical site
correction to get the final ground motion simulation.
•The biases of the stochastic simulation results compared withobservation are around the same compared with the GMPE
simulation.
•Effects from the magnitude level for source effects, groundmotion level for nonlinear site effects, and focal depth for
propagation path or direction should be considered in thefuture study.
2929

Joint Symposium of Seismic Hazard Assessment
June 17-21, 2013, Sendai, Japan

Thank you for your attention!
Kuo-Liang Wen
wenkl@earth.ncu.edu.tw30