Research Trends and Results

Functions road networks need to support disastervictims of a large-scale earthquake
MABUCHI Toshiaki, Senior Researcher
KANEKO Masahiro, HeadKIMURA Yuji, Senior Researcher
Earthquake Disaster Prevention Division, Research Center for Disaster Management(Key words) Earthquake, disaster response, road network
1. Introduction
When an earthquake occurs, many disaster responseorganizations take a variety of disaster response
actions including searching for missing people, firstaid and life-saving, fire-fighting activities, medical
treatment, and supplying water, food, and medicalsupplies in order to assist the victims of the disaster.
In order to take these disaster response activities, itis necessary for the people who perform first aid andlife-saving activities, water food and other materials to
be moved or transported from outside the disaster area
into the disaster area; an activity in which road
networks play an important role.
This research was done by collecting information
about various types of disaster response activities bymany organizations, organizing the correlation ofvarious disaster response activities with moving andtransporting people and materials, and evaluating thefunctions which a road network must have to ensuresmooth movement and transport.
2. Organizing response activities by different
organizations during a disaster
Based on the 9 categories of disaster emergency
measures in the Basic Disaster Prevention Plan(editedbytheCabinet
Office),theresearchers
comprehensively collected all kinds of disaster
response activities from legally required plans of allorganizations that respond to disasters (prefectures,cities, police, fire departments, Self-defense Forcesetc.), from disaster prevention related plans(guidelines, BCP, disaster prevention work plans,disaster prevention project plans etc.) and from actual
actions taken in response to the Great East Japan
Earthquake, and abstracted and organized about 250
activities that roads can support based on thecharacteristics of various modes of transportation(speed, capacity, mobility, etc.).
Next, they categorized the abstracted activities
according to purpose such as “ensuring traffic toperform emergency transport”, and organized thequestion, “What is transported from where (base) towhere (base)?” for all the approximately 250
activities.

Example of Response Activities in Iwate
Prefecture

3. Evaluation of road networks focused on disaster
response activities
An attempt was made to evaluate the functions of aroad network as emergency transport roads1) in Iwate
Prefecture. Here, the range of the hypothetical disasterregion was set with reference to the Great East Japan
Earthquake.
The figure presents a case of evaluation of functions
done by selecting, as the example of a disaster
response activity, movement from a base (regional
office of a prefecture outside the disaster region) to abase (city, town or village office in the disaster region)
as the “movement of people to support the opening ofroads”.
The combination of the bases (regional offices of aprefecture) (■mark) and bases (city, town or villageoffices) (●mark) was set based on distance and thedegree of relevance at normal times, and the roads formovement between the bases were selected as theshortest routes. And the degree of overlapping ofroads linking the bases was represented by the
thickness of the lines in each section of the road
network.
Roads represented by thick lines in the figure areroads necessary for “movement of people to support
the opening of roads”, and sections are evaluatedassuming that the thicker the lines, the more importantthe section. By representing other actions on the map
in the same way, for example, using those which
represent these superimposed on other purposes, it ispossible to evaluate the functions a road networkneeds to support disaster victims[Sources]
1. Iwate Prefecture Regional Disaster Prevention Plan(March 2012)