Earthquakes and Buildings

Taiwan is in the "Pacific Ring of Fire", the earthquake zone that surrounds the Pacific Ocean. Taiwan has more than 2000 earthquakes in a single year of which more than 200 are strong enough to be felt. Seattle is also in this "Ring of Fire" but I can only remember feeling one earthquake in the 20 years that I have lived there.

There have been several major earthquakes in Taiwan.


Date                Location                  Magnitude   Dead      House                         Name
                                                                                   Destroyed

21-Apr-35	Hsinchu, Taichung	7.1	3,276	17,907	1935 Hsinchu-Taichung earthquake
17-Jul-35	Hsinchu, Taichung	6.2	44	1,734
17-Dec-41	Chiayi	7.1	358	4,520	1941 Zhongpu earthquake
5-Dec-46	Tainan	6.1	74	1,954	1946 Xinhua earthquake
22-Oct-51	Hualien	7.3	68		1951 East Rift Valley earthquakes
15-Aug-59	Pingtung	7.1	16	1,214	1959 Hengchun earthquake
13-Feb-63	Yilan	7.3	3	6	1963 Su-ao earthquake
18-Jan-64	Chiayi, Tainan	6.3	106	10,924	1964 Baihe Earthquake
24-Apr-72	Hualien	6.9	5	50	1972 Ruisui earthquake
16-Sep-94	Taiwan Strait	6.8	0	0	1994 Taiwan Strait earthquake
21-Sep-99	Island-wide	7.3	2,413	51,711	921 Earthquake
26-Dec-06	Pingtung	7	2	3	2006 Hengchun Earthquake
4-Mar-10	Kaohsiung	6.4	0		2010 Kaohsiung

As you can see the last major earthquake in Taiwan was the "911 Earthquake". Although few of the earthquakes have had their origin near Taipei, it's interesting to speculate what kind of damage might occur. Of course, modern buildings are built with earthquake resistance in mind. During the 921 Earthquake, only one major building collapsed in Taipei and an investigation show that substandard materials and methods were used in it's building. Several of the builders and government inspectors went to jail.

A tall(101 stories) building like E101 in Taipei will have several top floors containing counter balances to resist movement.

 Some modern building will have the bracing made as part of the design.

 For older buildings, they are not as tall and they are built with no space between them and their neighbors. So the effect is to be a continuous low, long building.

 So their neighbor's building is part of their support group. But as their neighbors move away, maybe they are not as secure.

 For older buildings(more than 100 years old) they were build without much concern for earthquakes as earthquakes happened at the wimp of the Gods. In the old WanHua neighborhood of Taipei, there are several such buildings being restored. The materials then were not like today.

 Probably the only way to protect them from earthquakes is to use restraining girders.

 And make the girders as unobtrusive as possible.

 But this decoration might have been an early attempt at earthquake resistant building. I don't know.