NUMERICAL ANALYSIS OF WAVE FORCE ACTING ON BRIDGE DECK DUE TO TSUNAMI AND RESULTING MOTION OF BRIDGE DECK

Abstract

 The motion of a bridge deck due to a breaking bore is investigated numerically in terms of the horizontal and vertical components of tsunami force acting on the deck using a coupled fluid-structure-sediment interaction model. Numerical results show that the motion of the deck depends on the clearance below the deck and the weight of the deck because both horizontal and vertical tsunami forces acting on the deck are affected by the clearance below the deck and the static friction force acting on the deck is affected by the weight of the deck and the vertical tsunami force. As a result, the interaction between the deck, the horizontal tsunami force, and the vertical tsunami force is essential to assess the tsunami-induced motion of the deck. Furthermore, it is found that the horizontal tsunami force acting on the deck at the onset of the deck motion can be estimated from the horizontal flow velocity at the side of the deck when the deck begins to move by the bore hitting on the side of the deck.