Abstract
Revision of evacuation planning in consideration of forthcoming Tsunami disasters is a key issue in Japan. For this, authors have developed a path-based optimal evacuation planning model using space-time-extended network (STEN) that minimizes time to finish evacuation under the assumption that paths possibly used are enumerated in advance. The developed model needs a huge computational resource and a more computationally efficient model is needed to implement the model to a real situation. This study develops a link-based optimal Tsunami evacuation planning model. Referring to Jarvis and Ratliff (1982), it is proved that minimizing total evacuation time on STEN is equivalent with minimizing a time to finish an evacuation. This ensures that the link-based optimal evacuation planning model minimizing a total evacuation time provides an answer to minimize a time to finish an evacuation. We compared the result obtained by path-based and link-based optimal evacuation planning model, and the superiority of the link-based model has confirmed. Also the newly developed model gives useful information about shelters and links via Lagrangian multipliers, and the effect of enlarging shelters is discussed as an example.
