INTERNATIONAL INSTITUTE OF SEISMOLOGY AND
EARTHQUAKE ENGINEERING (IISEE)REPORT OF STUDY TRIP
(Niigata & Miyagi Prefectures)
14 – 17 November 2011
Prepared by: Liu RongS course(China)1

INTRODUCTION
Under the guide of our instructor Dr. Yokoi and coordinator Mr. Ajima, all participants of earthquake
engineering and seismology course had a study trip to Niigata and Miyagi Prefectures in Tohoku Areaof Japan from Monday, 14th November to Thursday, 17th November, 2011. Our itinerary includes
three cities or towns: Nagaoka City, Ojiya City, Sendai City and Onagawa Town. In Niigata Prefecture
which suffered the 2004 Chuetsu earthquake, we were given a lecture on the disaster and recovery of
the earthquake, and had a field trip to the disaster area. In Miyagi Prefecture, the focus of our study
trip was the 2011 Tohoku earthquake and tsunami. The remains in hit area showed us the horrors ofthe disaster. The lecture in Tohoku University helped us understand the causes and process of the 2011
Tohoku earthquake, the main methods of crust deformation observation and difficulties of earthquake
prediction. Through this study trip I got deep impressions about earthquake disaster emergency andrecovery in Japan. All of the knowledge is very useful and instructive for my country and my city.

NIIGATA PREFECTURE
Our travel began at the morning of Monday, 14th November. We went to Ueno station by Joban Lineand transferred to Joetsu Shinkansen. By the superexpress train, we got Nagaoka City in Niigata
within two hours. Niigata is the most famous rice producing area in Japan, the agriculture is welldeveloped. Along the way, the scenery of farmlands and mountains were very beautiful. The 2004
Niigata Prefecture Chuetsu Earthquake occurred here and caused great damages. After storing ourluggage at hotel, we first visited the Nagaoka Earthquake Disaster Archive Center.
Nagaoka Earthquake Disaster Archive Center
After the earthquake, the local government of Nagaoka City built lots of memorial halls andearthquake ruins parks, collectively referred to as the Chuetsu Earthquake Memorial Corridor.
Nagaoka Earthquake Disaster Archive Center is one important part of the “corridor”.
At first, Mr. Higuchi from the Regional Development Strategy Department of Nagaoka
City government gave us a lecture on the 2004 Chuetsu Earthquake, Disaster and Recovery: Theearthquake occurred on October 23rd, 2004. Although the magnitude was 6.8, not particularly large,
the intensity got upper 6 even 7 in some districts of Nagaoka. Nagaoka City was also the worst-hit area,
accounted for majority of the casualties and housing damage in Niigata Prefecture. Mr. Higuchi
showed us the newspapers at that time in his commentary (Fig 1.). I had an intuitive understanding of
the severity of the Chuetsu earthquake.
The recovery, reconstruction and development after disaster were the focus of the lecture.
Mr. Higuchi introduced us the Nagaoka City recovery plan and implementation programs at greatlength. The post-disaster revival was not only simple reconstruction and instauration, but also
comprehensive development. To formulate recovery plans, Nagaoka local government extensively
solicited and collected the views of the community: In addition to the Municipal Executive Council,

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the mayor organized the Recovery Committee composed of Scholars and professionals, and carriedout the forums with people in disaster areas. Government staff had repeatedly field survey and visit,etc. Finally, the recovery plan was carefully worked out, and constantly revised in the implementation.

Figure 1. Collections of the newspapers reported the earthquake disaster in
Nagaoka Earthquake Disaster Archive Center
According to the plan, the recovery of Nagaoka City was divided into three main parts:
boosting the public confidence in safety and security, revitalization and promotion of the economic
and social vitality of the affected areas, and sustainable development of mountain areas. As of 2010,
the restoration phase and resuscitation phase of the plan had already been completed. The mostimportant and basic parts of recovery plan, e.g. the anti-disaster reinforcement of traffic network, theensurement of the safety of mountains, rivers and residential houses, the repair and update of public
facilities had implemented.
After the lecture, we observed thevideo and image data of the Chuetsu
Earthquake

disasterinNagaoka

Earthquake Disaster Archive Center.
In the hall of the center, a Chuetsu
Region satellite map which almost
covered the entire floor attracted ourattention. At that time, the staff of thecenter distributed the ipad Tablet PCto each of us. Under their guidance,
we found that we could identify theFigure 2. Getting the information of the Chuetsu Earthquake

affectedareas

disaster area on the detailed satellite map by ipad

identified

onarethespecificallysatellite

map

through the ipad camera (Fig. 2).

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When we touched a selected area on the ipad screen, the local disaster information would be retrieved
and displayed: seismic intensity, casualties, building damage, and the comparison photos before andafter earthquake, etc.
This earthquake disaster information display by using advanced IT technology is very
innovative and vivid. I have never experienced before. I think that all the participants must be
impressed with the disaster. In my country, the propaganda of earthquake knowledge for public, justthrough simple pictures and video, is relatively backward. This new approach is very worthy forreference.
Ojiya General Hospital, Base Isolated Building
After leaving the Nagaoka Earthquake Disaster Archive Center, we came to the Ojiya General
Hospital to learn some knowledge about the base isolation and vibration control structure of building.
Ojiya is a small city on the south of Nagaoka, where the Chuetsu Earthquake intensity level reached
upper 6. The Ojiya General Hospital is located in the downtown of Ojiya city. In the earthquake, themain building of the hospital located at the edge of a hilltop was severely damaged. But the nearbybuilding Suisen-no-ie (Welfare Nursing Care Center, Fig.3), which just located at the foot of the hill,
was almost not affected.
In the basement of Suisen-no-ie, structural engineer Mr. Shinozaki introduced the baseisolation system of the building (Fig.4). Although I did not learn something about Earthquake
Engineering, I and other participants of seismology course were interested in the lecture. Through Mr.
Shinozaki’s explanation, I basically understood the concept and principle of base isolation structure.
Relative to the cost of buildings, this system was not too expensive. But it can be very effective toresist strong motion, and protect buildings.

Figure 3. Welfare Nursing Care Center (Suisen-no-ie) ofFigure 4. Base isolation system ofthe Ojiya General Hospital

Suisen-no-ie4

Yamakoshi District
November 15th was the second day of our study trip. In the morning, we visited the Yamakoshi
District of Nagaoka City. The name Yamakoshi had been heard and seen many times in the Nagaoka
Earthquake Disaster Archive Center. It is a small mountain village near the epicenter, whose intensity
reached upper 6 in the 2004 Chuetsu earthquake. In order to learn details of the earthquake damage inthis village, we first visited the Yamakoshi Branch Office.
Staffs of the office were very hospitable to us. In the conference room, they introduced thesituation of the disaster and recovery work of Yamakoshi village: There were five people died in theearthquake, 25 people were injured, and about 1,500 dwelling houses were damaged. The slope
failures and landslides blocked roads and rivers, all communications were interrupted. All of the morethan 2000 residents of Yamakoshi village were transferred by the helicopters of the Japanese
Self-Defense Force.
It was about to be winter at that time.
According to introduction, the snowfall could
reach 3 to 4 meters every year in this place(Fig.5). Therefore, the victims' lives were very
difficult. Some people had to eat their expensive
Nishikigoi Carps to stave off hunger.
Fortunately, the disaster-hit area got help frommany parts of Japan in a timely manner.
Professional
emergency
rescueteams,volunteers and relief supplies arrived soon.
1,755 evacuees from Yamakoshi moved into the631 temporary houses in Nagaoka City. They
got meals prepared by volunteers.
Now, with the implementation of
the Nagaoka City recovery plan, the resuscitation

Figure 5. Snow disaster after the 2004 Chuetsu

of Yamakoshi has been basically completed.

earthquake in Yamakoshi (taken in the Nagaoka

Over 70% of the residents have moved back toEarthquake Disaster Archive Center)the village and start their new lives.
After the presentation, time was approaching noon. Accompanied by a staff of theYamakoshi Branch Office, we visited the remains of the earthquake, the residential houses built bygovernment and the aquaculture industry in Yamakoshi.

5Figure 6. The landslide and barrier lake caused by the Chuetsu earthquakein Yamakoshi Village

Collapse of the housing had been cleared long ago. The roads and tunnels had also beenrepaired. Even most of the failured slope of the mountain had been reinforced and re-planted
vegetation. Wounds caused by the earthquake here were difficult to see now. But we still saw theremains of barrier lakes and landslides (Fig.6). The houses soaked in water in those days had beenabandoned for a long time; almost buried to the roof by the soil taken by flood and surrounded byovergrown weeds.

Figure 7. Model units built by government in Yamakoshi6We then visited the model residential houses for the victims (Fig.7). These houses werebuilt by government with excellent quality. Both exterior and interior are very beautiful. And theconstruction costs are cheap. The residents who cannot afford the construction costs will also be
provided financial assistance.
Yamakoshi village is famous for its bullfighting and Nishikigoi carps. Unfortunately, thetime we visited here was not in the bullfighting season, so we missed to enjoy the very unique culture.
In carp farms, we saw the very beautiful Nishikigoi which is one of the Japanese national treasures.
Yamakoshi people’s optimism of life and love of the traditional culture deeply impressed us.

MIYAGI PREFECTURE
In the afternoon, we left Yamahoshi District. So far, half of our trip had passed. We changed Joetsu
Shinkansen to Tohoku Shinkansen at Omiya station, and then went to Sentai City in Miyagi. Dr. Hara
joined us here. When we arrived at Sendai, it was already evening. Sendai is the capital of Miyagi
Prefecture, and is the political and economic center of Tohoku Region. Sentai City and the coast ofMiyagi are the hardest hit areas of the 2011 off the Pacific coast of Tohoku Earthquake and tsunami.
The serious damage in this disaster is the theme of our study trip here.
Sendai 3rd Joint Governmental Building
In the morning of Wednesday, 16th November, we first visited Sendai 3rd joint governmental building.
This building was constructed in 1978. In 2007 to 2009, it was retrofitted to install the base isolator
system. In the basement floor, we saw a seismoscope that uses a needle to record the trace of building
vibration on a plastic plate. In the Tohoku Earthquake, It recorded the maximum displacement 18 cm(Fig.8). According to the staff, some seismoscopes at other places were broken during the shaking
caused by the power of the shock. The needles couldn’t turn back into the original position.

Figure 8. Displacement monitoring plate

Figure 9. Minor damage of Sendai 3rd joint

seismoscope

governmental building

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Because of the the base isolator system, the main structural part of this building was almost
not affected in the earthquake. Only some of the non-structural elements were dameged such as thefire resistant material (Fig.9).
Tohoku University, Research Center for Prediction of Earthquake and Volcanic Eruption
The Research Center for Prediction of Earthquake and Volcanic Eruption in Tohoku University was
our next destination. Professor Norihito Umino received us. Before his lecture, Professor Umino led us
to visit this research center. The center has a long history, can be traced back to 1912, when it wasestablished for monitoring earthquake. There are many old types of instrument for earthquake
monitoring and precursor observation (Fig.10). Some of them are no longer used, just kept ashistorical data, such as the Wiechert Seismometer. Some of them still work now.
In the tunnel under the research center at depth of 45m, we saw some crust deformation
observations, such as water tube tiltmeter, quartz tube strainmeter, quartz pendulum tiltmeter and so on.
Professor Umino explained the principles of these observations to us. My personal focus of work
exactly is the crust deformation. The same or similar observation instruments are also used in my city.

Figure 10. Instruments for earthquake monitoring and crust deformation observation in the ResearchCenter for Prediction of Earthquake and Volcanic Eruption(Left: The Wiechert; Middle: Water tube tiltmeter; Right: Quartz tube strainmeter)
Professor Umino gave us a lecture in a small meeting room: At first He began with a brief
history of the Research Center for Prediction of Earthquake and Volcanic Eruption. Then combinedwith the great Tohoku Earthquake he talked about the difficulties of earthquake prediction. In his view,
various theoretical models of generation Mechanism of Earthquakes are too simple at present. In
current theory, it is said that giant earthquake generally occurs in young oceanic plate subduction
boundary. But the fact of great Tohoku Earthquake is contradicted: The age of the Pacific plate atnortheast of Japan is old. The reason of Tohoku Earthquake cannot be explained well. Professor
Umino encouraged us to study hard, and explore further in the future.

8Onagawa Town
Onagawa town is located in Oshika District, at the northeast corner of Miyagi Prefecture. In theTohoku earthquake and tsunami, it was heavily damaged. Under the effect of the superposition, theheight of the tsunami in the shallow Onagawa bay got as high as 15 meters. The terrain of the town isflat without sufficient embankments or seawalls. All area within 3 kilometers inland was inundated.
And most of the houses were swept away or overturned by the tremendous tsunami.
As shown in left of Figure 11, a hospital on the hill was located approximately 14 meters
high from the below ground. Its first floor was all immersed in the tsunami. Most of the buildings near
the seashore were completely destroyed by the strong waves, only left their foundations or ruins(Fig.11). Some of the places in Onagawa town were still covered by sea water. Dr. Yokoi told us there
were over 1000 people missing, more than 700 confirmed dead in the disaster. Before coming to Japan,
I had read a touching story happened here in Chinese newspapers: A director of a fish processing
company named Sato saved his workers and 20 female Chinese resident trainees. He evacuated themto higher ground, but he was swept away.

Figure 11. Ruins in the Onagawa town after the tsunami swept through(Left: Residual bases and the hospital on the hill; Middle upper and lower: Completely uprooted anddestroyed buildings; Right: A three floors hotel facing the sea was totally inundated)
Sendai City: Tohoku Regional Development Bureau, Aoba Ward and Wakabayashi Ward
November 17th was the last day of our trip. The itinerary began at Tohoku Regional Development
Bureau in Sendai City. We were given a lecture of emergency and recovery of “Eastern Japan Great
Earthquake Disaster”. A lot of tragic scenes from closed-circuit televisions and helicopter aerial
photography at Sendai were showed to us. Facing of helpless people in the video, I almost could not
bear to look. The efficiency of the disaster response was amazing. According to report, just within oneweek, 97% of the national high ways in Tohoku were cleared up to ensure the rescue teams and relief
supplies accessing the disaster area timely. When the quake happened, the Sendai airport had
immediate subsidence and then was badly flooded by the subsequent tsunami. Besides submerging the9tarmac and runway, the water reached up to the 2nd floor of the passenger terminal. But on 13 April
2011, only one month later, the airport had reopened.
In the Aoba Ward of Sendai, we observed the ground failure caused by the quake. Theresidential area we visited was on a hill. Yokoi Sensei told us the ground of this area was made byearth-fill. The building bases here were not strong enough to resist the severe shake in the Tohoku
Earthquake. As shown in Figure 12, the road had split and deformed. The walls along the ramp hadtilted or collapsed. Because of the landslide, some houses on the hillside sank and almost tumbled
down.

Figure 12. A residential area in Aoba Ward destroyed by the earthquakeWakabayashi Ward was the last destination of our trip. This ward is located in thesoutheast coast of Sendai City. It was also severely damaged. As the same as Onagawa Town, a broadand barren ground came into view. There were only ruins of houses and some boulders washed ashoreby the tsunami. Such a huge destructive power was beyond my imagination.

COMMENTS and CONCLUSIONS
The first visual impression I got in this study trip was that facing the overwhelming power of nature，
human beings were so weak and helpless. Although scientists have made a lot of explore on
earthquake prediction, we have to admit up to now the accurate forecasting of earthquake isimpossible. However, these facts do not mean we have nothing to do but only wait for disaster. During
this trip, I found that all the preparation of pre-disaster and the disaster emergency and recovery are
well taken into account and meticulously implemented. Without these measures, I can image that thedisaster losses will grow exponentially. In my opinion, all these practices are worthy of learning forthe disaster mitigation. The innovative and vivid disaster education on earthquake and tsunami for thepublic is vital; the advanced base isolation and vibration control structure should be promoted in China.
The government-led reconstruction and recovery should be more humanized and systematic.

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REFERENCES
1. Niigata Chuetsu Earthquake on October 23, 2004. 地震調査研究推進本部（文部科学省研究開発局地震・防災研究課）
http://www.jishin.go.jp/main/chousa/04oct_niigata/index-e.htm
2. The 2011 off the Pacific coast of Tohoku Earthquake. 日本建築学会災害委員会
http://bousai.env.nagoya-u.ac.jp/wiki/saigai/index.php?The%202011%20off%20the%20Pacific%20coast%20of%20Tohoku%20Earthquake
3. Immense heroism of ordinary people offers ray of hope in stricken Japan
http://www.irishtimes.com/newspaper/world/2011/0326/1224293136126.html
4. Cigdem Tetik, Nolan Evangelista and Mehmet Baykal (2010-11 Seismology Course). Onagawa
Town Observation.

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