RED-ACT Report: Jan 26, M4.4 Japan Kumamoto

RED-ACT Report

Real-time Earthquake Damage Assessment using City-scale Time-history analysis

Jan. 26, Japan Kumamoto-ken Kumamoto-chiho Earthquake

Research group of Xinzheng Lu at Tsinghua University

luxz@tsinghua.edu.cn

First reported at 13:50, Jan. 26, 2019 (Beijing Time, UTC +8)

Acknowledgments and Disclaimer

The authors are grateful for the data provided by K-NET and KiK-net. 

This analysis is for research only. The actual damage resulting from the earthquake should be determined according to the site investigation.

1. Introduction to the earthquake event

At 14: 16, Jan. 26, 2019 (Local Time, UTC +9), an M 4.4 (JMA) earthquake occurred in Kumamoto-ken Kumamoto-chiho, Japan. The epicenter was located at 33.0N, 130.6E, with a depth of 10.0 km. The maximal recorded peak ground acceleration (PGA) is 95cm/s/s.

2. Recorded ground motions

20 ground motions near to epicenter of this earthquake were analyzed. 

No. Station Name Longitude Latitude

1 FKO011 130.512 33.3235

2 FKO013 130.561 33.2252

3 FKO014 130.818 33.1491

4 FKO015 130.405 33.1627

5 FKO016 130.447 33.0159

6 KGS001 130.176 32.1947

7 KMM001 131.069 33.1208

8 KMM002 130.685 33.0185

9 KMM003 130.548 32.9336

10 KMM005 130.877 32.8761

11 KMM008 130.658 32.6878

12 KMM009 130.989 32.6864

13 KMM011 130.865 32.6167

14 KMM012 130.602 32.5078

15 NGS012 130.346 32.7884

16 NGS014 130.185 32.6106

17 OIT005 131.114 33.4549

18 SAG003 130.207 33.373

19 SAG005 130.064 33.3213

20 SAG007 130.3 33.2627

3. Seismic damage analysis for target region subjected to the recorded ground motions

Using the real-time ground motions obtained from the strong motion networks and the city-scale nonlinear time-history analysis (see the Appendix of this report), the damage ratios of buildings located in different places can be obtained. These damage ratios can provide a reference for post-earthquake rescue work. The damage ratio distribution of the buildings near to different stations is shown in Figure 1. The human comfortableness distribution near to different stations is shown in Figure 2. 

The details can be accessed at 

http://www.luxinzheng.net/software/2019-01-26-Japan-4.4.html

http://www.luxinzheng.net/software/2019-01-26-Japan-4.4-Acc.html

Figure 1 Damage ratio distribution of the buildings near to different stations

Figure 2 Human comfortableness distribution near to different stations

附：党纪教授发来的日方分析结果