THE DISASTER DUE TO THE MARCH ELEVEN 2011 EAST JAPAN
EARTHQUAKE AND TSUNAMI
36th Our World in Concrete and Structures (OWICs) - 2011
Shoji Ikeda*, Akira Hosoda and Kazuhiko Hayashi
Earthquake, Tsunami, Nuclear reactor, Radioactivity, High-rise artificial land
There happened a great earthquake of Magnitude 9.0 in the eastern part of
Japan in March 11, 2011 followed by a mega tsunami. The earthquake of M9.0 was
the highest magnitude in the history of Japan so far. The vast regions of eastern
Japan were devastated mainly by the mega tsunami. More than twenty thousand
people were dead or missing although certain precautious countermeasures were
provided. In addition, reactors of a nuclear power station after emergency shutdown
became out of control due to the complete loss of electricity by invasion of the
tsunami water into the facility. Eventually, radioactive materials were spread
according to the hydrogen explosions and contaminated the surrounding areas.
From these fatal experiences, many important lessons and urgent countermeasures
for future hazards can be drawn as follows:
It would be almost impossible to avoid the damage in conventional cities at present
due to mega tsunamis so that careful and deliberate countermeasures should
urgently be prepared to protect human lives according to local specific conditions.
The mega tsunami occurs once in several hundred years. Therefore, we must review
the history of disaster in the local specific areas. The past mega tsunami could be
found by digging the layer of the ground.
High-rise artificial land should be built with highly durable concrete structures as soonas possible in tsunami anticipating areas.
Reliable warning systems are essential for the evacuation in case of the tsunami and
earthquake. Education and exercise are the most effective countermeasures.
The alert system of emergency train stop was successfully ordered in this particular
disaster in Japan. Therefore, no derailing was seen during the earthquake.
Nuclear power plants should be properly protected against any kind of disturbances
such as terrorism, earthquake and tsunami without exception.
Electricity is essential next to the air, then, atomic energy should be properly
Modern life cannot exist without electricity.