Modification of an Assessment Model for Post-Earthquake Lifeline Serviceability

Abstract

The assessment model for post-earthquake serviceability of utility lifelines had been proposed and validated by authors. However, the model tends to slightly overestimate the time required for restoration with some earthquakes. Therefore, in this paper, we examined a method to improve the accuracy of the estimation model focusing on the fact that the difference in disaster scale affects the time required for restoration. We define two indicators: the first represents the ratio of observed to the estimated value using cumulative affected population. The second represents the disaster scale using weighted PEX (Population Exposure to shaking intensity). Based on the relationship between the two indicators, estimated values of time required for restoration in electric power and water systems are corrected to agree with observed values. It is shown that the accuracy of estimation for the major earthquakes tends to be improved the time required for restoration.