DAMAGE OF BRIDGE STRUCTURES BY HUGE TSUNAMI AND EVALUATION OF TSUNAMI FORCE ON BRIDGES

This paper introduces what damage we had by the huge earthquake and tsunami broken out on 11th March, 2011, and what we have been working for determining the tsunami force having acted on bridge structures. Right after the happening JSCE sent the delegation to survey how serious the damage was. Based on the brief surveying report, JSCE concrete committee decided to set up a research committee (1) to examine what has happened in bridge structures and (2) to study the tsunami force having acted on bridge structures. With help of Internet photo service all bridges within inundation areas were examined whether they were in safe or were washed away. Combined with on site survey the total number of washed away bridges has been determined. Details of bridges have been collected by asking authorities who have been taking care of bridges. Taking the location and dimension of a bridge as well as assumed tsunami velocity, the tsunami force having acted on the bridge is to be studied. Unfortunately, the work does not yet get to the goal