Wave Force Acting on Bridge with Cross-section of Concave Shape

The wave pressure and wave force acting on a model bridge with a concave cross-section are measured. The characteristics of the wave pressure acting on the underside of the model bridge depend on the wave breaking. The wave pressure caused by the air compression is measured at the concavities on the underside of the model bridge under the non-breaking wave condition. The maximum wave pressure caused by the air compression is much larger than that without the air compression.

A huge tsunami struck the northeastern coasts of Japan on March 11, 2011. The tsunami caused a catastrophic damage to the coastal zones. Many bridges as well as buildings were washed away by the tsunami. The transportation of relief was delayed in many areas because many bridges were washed away. The tsunami wave force acting on bridges has not been taken into account in the present design in Japan. Therefore, the stability and the countermeasures of bridges against tsunamis have to be investigated.