INVESTIGATION ON DESTRUCTIVE POWER INDICES OF STRONG GROUND MOTIONS USING BUILDING DAMAGE DATA AND STRONG GROUND MOTION RECORDS BY THE 1994 NORTHRIDGE, CALIFORNIA, EARTHQUAKE

This study presents strong ground motion simulation methods for the future fragility study of a power plant in Southern Taiwan. The modified stochastic method and empirical Green function method are utilized to synthesize the strong ground motions of specific events. A modified physical random function model of strong ground motions for specific sites and events is presented in this study with verification of sample level. Based on the special models of the source, path, and local site, the random variables of the physical random function of strong ground motions is obtained. The inverse Fourier transform is used to simulate strong ground motions. For the empirical Green function method, the observed site records from small earthquake events occurring around the source area of a large earthquake are collected to simulate the broadband strong ground motion from a large earthquake event. Finally, an application of proposed two simulated methods of this study for simulating the ground motion records of Nishi-Akashi Station at 1995 Kobe earthquake and 2006 Southern Taiwan PingDong earthquake are presented.

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RE-ESTIMATION OF STRONG GROUND MOTION IN NADA WARD BASED ON INVENTORY AND BUILDING DAMAGE DATA

Journal of Structural and Construction Engineering (Transactions of AIJ) ◽

10.3130/aijs.64.141_5 ◽

1999 ◽

Vol 64 (523) ◽

pp. 141-148 ◽

Cited By ~ 5

Author(s):

Osamu MURAO ◽

Fumio YAMAZAKI

Keyword(s):

Ground Motion ◽

Strong Ground Motion ◽

Building Damage ◽

Damage Data ◽

Strong Ground

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Identification of Near-Field Pulse-Like Ground Motions Recorded at Bajiao Station during the Mainshock of the Great Wenchuan Earthquake

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.250-253.2546 ◽

2011 ◽

Vol 250-253 ◽

pp. 2546-2553 ◽

Cited By ~ 2

Author(s):

Chun Feng Li ◽

Yong Bo Li

Keyword(s):

Wenchuan Earthquake ◽

Ground Motion ◽

Strong Ground Motion ◽

Ground Motions ◽

Near Field ◽

Velocity Pulse ◽

Field Pulse ◽

Near Fault ◽

Ground Motion Records ◽

Strong Ground

When earthquake occurs, it is in near-fault that the most serious damage happens and velocity pulse appears. Velocity pulse could have huge potential to destroy the structure in near-fault. The set of records at Bajiao Station is one of the three famous near-field sets of strong ground motion records whose PGAs are the largest in all the sets of records obtained from the mainshock of the Great Wenchuan Earthquake. Our research is to identify the pulse-like characteristics from the set of records at Bajiao Station. It is found that velocity pulses in the records are “hidden pulses”.

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Analysis of Site Amplification and Nonlinear Response Based on Ground Motion Records at MYGH10 Station in Japan

10.21203/rs.3.rs-1122308/v1 ◽

2021 ◽

Author(s):

Shiliang Zhang ◽

Dongwang Tao ◽

Quancai Xie ◽

Qiang Ma ◽

Fuchen Wang

Keyword(s):

Ground Motion ◽

Amplification Factor ◽

Ground Motions ◽

Spectral Ratio ◽

Site Amplification ◽

Predominant Frequency ◽

Strong Ground Motions ◽

Ground Motion Records ◽

Site Amplification Factor ◽

Strong Ground

Abstract Strong horizontal ground motions with the peak ground acceleration (PGA) larger than 1400 gal were observed at Yamamoto (MYGH10) station during the February 2021 Mj 7.3 off the east coast of Honshu, Japan, Fukushima earthquake. Firstly, in this paper, we discussed and verified the theoretical assumptions of the “Nakamura” method under weak and strong ground motions. The site amplification factor of the MYGH10 station was estimated using the surface horizontal-vertical spectral ratio (HVSR) and the surface-to-borehole spectral ratio (SBSR), and the corrected HVSRC, respectively. Meanwhile, the reasons for underestimating the site amplification factor when using HVSR were explained. The vertical amplification phenomenon of seismic P-wave in the high-frequency band was analysed under weak and strong ground motions. Secondly, we utilized HVSR, SBSR, and theoretical transfer function (TTF) based on the 1D wave propagation theory to study the nonlinear site response of MYGH10 station under the mainshock of the Fukushima earthquake and the historically weak and strong ground motions, respectively. The changes in frequencies and amplitudes of the spectral ratio curves when nonlinearities were occurring at the site were analysed and compared using the spectra ratio curves of weak ground motion records and TTF as references. Finally, the recovery of the site after strong nonlinearity was also evaluated by comparing the spectral ratio curves of aftershocks records. We found that the most significant amplification factor of the site increased from 7 to more than 10, and the predominant frequency decreased from 10 Hz to 3.8 Hz under the mainshock of the Fukushima earthquake. The predominant frequency returned to the previous value within three days after the mainshock, but the amplification factor did not.

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Broadband Strong-Motion Prediction for Future Nankai-Trough Earthquakes Using Statistical Green’s Function Method and Subsequent Building Damage Evaluation

Applied Sciences ◽

10.3390/app11157041 ◽

2021 ◽

Vol 11 (15) ◽

pp. 7041

Author(s):

Baoyintu Baoyintu ◽

Naren Mandula ◽

Hiroshi Kawase

Keyword(s):

Green’S Function ◽

Green's Function ◽

Nankai Trough ◽

Ground Motions ◽

Building Damage ◽

Steel Buildings ◽

Ground Acceleration ◽

Attenuation Relations ◽

Strong Ground Motions ◽

Strong Ground

We used the Green’s function summation method together with the randomly perturbed asperity sources to sum up broadband statistical Green’s functions of a moderate-size source and predict strong ground motions due to the expected M8.1 to 8.7 Nankai-Trough earthquakes along the southern coast of western Japan. We successfully simulated seismic intensity distributions similar to the past earthquakes and strong ground motions similar to the empirical attenuation relations of peak ground acceleration and velocity. Using these results, we predicted building damage by non-linear response analyses and find that at the regions close to the source, as well as regions with relatively thick, soft sediments such as the shoreline and alluvium valleys along the rivers, there is a possibility of severe damage regardless of the types of buildings. Moreover, the predicted damage ratios for buildings built before 1981 are much higher than those built after because of the significant code modifications in 1981. We also find that the damage ratio is highest for steel buildings, followed by wooden houses, and then reinforced concrete buildings.

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