The drift behavior of a shipping container on an apron resulting from a tsunami-induced incoming flow and subsequent return flow is investigated using hydraulic experiments and numerical simulations. Experimental and numerical results show that the container initially set parallel to a quay wall can fall into the sea when the relative overflow height of an incident tsunami is large regardless of the relative initial position of the container. This suggests that it is not always effective to

more »

... ter containers near the seawall before large tsunamis. In addition, it is not evident that the container initially set perpendicular to the quay wall drifts seaward, suggesting that an effective countermeasure would be to store containers on the apron in the cross-shore direction.