Study Trip Report onHIYORIYAMA PARK and ISHINOMAKI TAX OFFICE
By: Herrera Puma Dina Bilha, Martinez Bravo Delvin Abdiel, Qi Wen-Hao (E-Course)

Introduction
This technical report shows the observed damages which were caused by the 2011 off the Pacific coast ofTohoku Earthquake in three sites visited during the study trip organized for the IISEE training course by
BRI and JICA. The visit was realized on September 6th, 2011, six month after the great earthquake.
The damages found were mainly due to the tsunami which destroyed several towns located along
the coast line, including industrial facilities, houses, hospitals, schools, among others. The sites visited arefollowing:
1. Hiyoriyama ParkThe Hiyoriyama Park is located on the top of a high hill, 56-meter-high, in the center of Ishinomaki City.
The park was a gathering and evacuation place for many of the local population on the day of the disaster,March 11th. Many people witnessed from this vantage point as the tsunami took over their town.
From that point, we could see a huge area that had been devastated by the tsunami such as Minatoarea and surrounding areas of Ishinomaki. The difference in tsunami damage was quite clear. The view
from Hiyoriyama Park to the left side of Ishinomaki Port was protected by a seawall, so it did not suffer
heavy damage. The right side of Ishinomaki Port, including the district of Kadowaki-cho, suffereddevastating damage. We were able to see toppled homes and bare foundations.

Photo 1. (left) The area on the left side of Ishinomaki port was protected by theseawall and suffered minor damage. (center) The view of Ishimaki port. (right) The
area devastated by the tsunami.
2. Liquefaction on the site of Ishinomaki Tax Office
Liquefaction is one common disaster due to earthquakes.
The typical phenomena of liquefaction are water
spraying and sand emitting. If liquefaction occurs insome sites, the foundation soil will lose one part or eventotal bearing force, and uneven settlement of the soil willtake place. Then the foundation will get damaged. Thus
the buildings and structures will incline or overturn assome buildings were damaged in the 1964 Niigata
earthquake of Japan (Photo 2).
Photo 2. Liquefaction in 1964 Niigata Eq. (USGS)
During the 2011 Tohoku Earthquake,many places had liquefaction phenomena, e.g. thesite of the Ishinomaki tax office where the typical phenomena of liquefaction occurred. The officebuilding inclined about an angle with 1/80 (Photo 3), and the ground in front of the building became outof-flatness due to the uneven settlement of foundation soil (Photo 4). The foundation soil became moreclose-grained due to liquefaction and larger settlement occurred, so some RC water tanks (Photo 5) andother facilities cropped out the ground (Photo 6).

Photo 3. Inclined building

Photo 5. Outcropping RC water tank

Photo 4. Out-of-flatness groundPhoto 6. Outcropping steel facilities

3. Ishinomaki city
Ishinomaki City, Miyagi Prefecture, is located approximately 45 km to the northeast of Sendai City
(Japan Times, March 14th 2011). Due to the 2011 off the Pacific coast of Tohoku Earthquake, this city
was totally destroyed, mainly by tsunami.
The more important income of this city is from the fishing activity, due to its location in the coastline, in front of the Pacific Ocean. All the facilities dedicated to the fishing activity were severely
damaged by the tsunami. According to the report from the Port and Airport Research Institute, thetsunami height was 5 m at Ishinomaki Harbor, and 16 m at Ogatsu-machi, Ishinomaki City (Architectural
Institute of Japan, April 15th 2011). The Tsunami traveled around 600 meters inland and destroyed
around 80% of the houses (Japan times, March 18th 2011). Most of them were wooden houses which weretotally destroyed by the earthquake and the following tsunami (Photo 7 and 8).

Photo 7. View of the Ishinomaki City, 6month after the great earthquake.

Photo 8. Severe damage caused by Tsunami
to a wooden house in Ishinomaki city

The important structures, like hospital (Photo 9) and School (Photo 10), in this city were severely
affected by the earthquake and then struck by the following great tsunami. These structures areindispensable in the case of emergency; the hospital to attend the injured people and the school can beused as a shelter.

Photo 9. Hospital in Ishinomaki city
severely damaged by earthquake andtsunami

References
Photo 10. Kadowaki elementary school,

completely destroyed, also due to fire.