地盤研究財団
Introduction Research and Activity
Research and Activity
Accumulation and utilization of Geotechnical information
Explore the geology
Understanding Earthquakes
Countermeasures against natural disasters
Subsurface investigations
Together with world
Base of Service Activities
 
TOP > Research and Activity > Countermeasures against natural disasters
Countermeasures against natural disasters
 

Prediction of ground disasters due to earthquakes and heavy rainfall and disaster prevention examination

Japan has experienced many large-scale natural disasters such as earthquakes and heavy rainfall. Therefore, preparing for those disasters (disaster prevention measures) is an extremely important issue in the construction of a living base. At the foundation, we conduct comprehensive surveys in cooperation with each technology division on prediction of ground disasters such as liquefaction during earthquakes and slope failures during heavy rainfall and disaster prevention.
Liquefaction potential prediction
Liquefaction causes great damage to buildings and lifelines. Since the Niigata earthquake (1964), liquefaction potential prediction has become a basic consideration for earthquake disaster prevention. This figure shows the liquefaction potential in the case of the Hyogo-ken Nanbu Earthquake, which was predicted based on the geotechnical information from about 8,000 boring logs. The results correspond well to the distribution of the liquefaction points.
Liquefaction prediction by boring data which assumed the 1995 Hyogo-ken Nanbu Earthquake
(Shin kansai Jiban – Ground of Kansai area especially Kobe to Hanshin (1998))
▲Sand injection points due to Hyogo-ken Nanbu Earthquake
(by information such as aerial photographs)
Earthquake damage predictions
Development of regional disaster prevention plan is carried out based on the prediction of various damage that occur to the local community by the assumed earthquake. We will be in charge of surveying Osaka Prefecture etc. when the disaster prevention plan for the direct earthquake was reviewed in each local government after the Hyogo-ken Nanbu Earthquake, and quickly introduced the strong ground motion prediction method using the fault destruction model. We made damage predictions based on lessons from the Hyogo-ken Nanbu Earthquake.
Survey on Road Earthquake Disaster Prevention
At the time of the earthquake, the road network is an important lifeline for prompt and accurate response regarding the lives and lives of victims, such as rescue and emergency, fire extinguishing, medical care, and supply of emergency living materials, as the core of emergency transportation. We conducts multi-faceted surveys that combine wide-ranging methods according to the purpose for examining road earthquake disaster prevention in a wide area or at a point.
Survey on rainfall slope disaster
During heavy rains caused by typhoons and rainy seasons, slope failures frequently occur, and it is not uncommon to cause damage to human lives. In this example, we conducted a survey on traffic control management under abnormal weather conditions in Hyogo Prefecture's road network, and from the perspective of regional disaster prevention, we used rainfall indicators (management criteria) to detect the occurrence of road slope disasters during heavy rainfall. This is an example examined based on 10 years of disaster data.

An example of the record of the rainfall that a road slope
disaster occurred and the transition of the rainfall index value
disaster point
■rainfall Observatory
▲Damaged sites on Hyogo Prefecture road slopes due to Typhoon No. 19, 1990 and distribution of 24-hour rainfall (at peak time) ▲Distribution of suitable rainfall intensity of rainfall index based on the disaster data of the past 10 years 〈Soil rainfall index〉
The larger the black circle(●), the higher the accuracy rate for past damage occurrences.
(Hyogo Prefecture Road Traffic System Maintenance Survey 2000-2001)



Geo-Research Institute
TOP