Abstract
, and Prevention of areas becoming cut-off by earthquakes is one of the most important countermeasures against urban seismic disasters. Isolated areas are caused primarily by damage to road bridges due to earthquake. Urgent seismic retrofit of existing road bridges is, therefore, necessary for us to prevent such bridges from seismic damage. For determinating the order of priority of seismic retrofit of bridges, this isolated area problem must not be neglected. From the above view, we developed a method for importance assessment of existing road bridges which places priority upon the prevention of areas becoming isolated and applied this method to Tokushima city.
