The collapse of Tsuyagawa bridge damaged by Tohoku Tsunami is numerically investigated using the Applied Element Method, due to its advantages of simulating structural progressive collapse. The analysis was proven to simulate the bridge collapse.  It showed that the bridge collapsed at a water speed of 6.6 m/sec initiated by flexural failure of its piers.  Study of bridge strengthening showed that the collapse water speed  could be increased by 22% and 29% compared to Tohoku tsunami if the piers are strengthened by a 100-mm RC thick steel jacked, respectively.

Salem, H, Mohssen, S., Nishikiori, Y., and Hosoda, A. (2015) Numerical Collapse Analysis of Tsuyagawa Bridge Damaged by Tohoku Tsunami. JCI Annual Convention, Chiba, Japan, July 2015, Vol. 37, No. 2, Pg. 55.