Lifeline Interrelationships during the Tohoku Earthquake: Management of Disaster Analysis Reports Using Text Mining

Abstract

Although many studies have been undertaken in the area of lifeline interrelation, examinations based on the quantitative evaluation of post-earthquake lifeline interrelations have been limited. In this study, we present a new methodology to evaluate lifeline interactions, with an emphasis on the aspects of earthquake disasters. Terms related to other lifelines used in disaster reports are somewhat influenced by postearthquake behaviors. In this study, the number of related terms was counted, and the relationships between the lifelines were quantitatively assessed for the 2011 Tohoku earthquake that occurred in Japan. The validation process included checks through academic reports as well as government reporting. We found that many lifelines were strongly dependent on the electric power systems, which gave no consideration to the accident at the Fukushima nuclear power plant. We confirmed further that the similar lifeline interrelation results could still be obtained regardless of the reporting used.