Estimation of Pickup Rate of Suspended Sand by Tsunami Experiment and Proposal of Pickup Rate Formula

Abstract

Pickup rate of seabed sand was estimated from the balance of suspended sediment flux obtained by tsunami experiment (Yoshii et al., 2008). Two nondimensional dominant parameters such as 'nondimensional sand grain diameter' and 'nondimensional settling velocity', were newly introduced. And a new pickup rate formula of suspended sand was proposed by using their two parameters and the Shield's number. Generally, the new pickup rate formula could reproduce the experimental results of two sand grain sizes, and pickup rates by the previous tsunami experiment (Takahashi et al., 1999) better than the conventional pickup rate formula. It was showed that the above formula was able to reproduce the experimental seabed topography deformation around a harbor due to tsunami better than the conventional pickup rate formula.