We study transport of sinking plastic debris induced by long solitary waves by means of laboratory experiments. Three succeeding breaking solitary waves propagate towards a sandy beach, and impact debris which are initially placed at different locations along the slope. The debris are just a little bit heavier than the water and are initially lying on the bottom, which is covered with the 2 cm layer of sand. The main measured parameter is the displacement of the debris along the slope, which is studied with respect to the initial position of debris, number of consecutive waves and the size of the sand.
Tsunami when approaching the coast carries multiple sediments, stones and debris of different size. These debris often reinforce hazardous impact of tsunami waves on coast and coastal structures, therefore it is very important to know their dynamics.
The propagation of single floating spherical debris in deep-water waves has been discussed by (Calvert et al, 2021). They concluded that the debris’ size relative to the wavelength dominates the drift. (Larsen et al, 2023) studied experimentally the transport of buoyant plastic particles with different shapes and densities in the nearshore and showed that their transport velocities are equal to the wave celerity. (Guler et al, 2022) studied dynamics of several plastic particles with different shapes, densities and sizes under breaking irregular waves, and showed that their final distribution was highly influenced by the Dean number, particle shapes, and the type of the bottom. (Kerpen et al, 2020) studied plastic particles of different size, shape, and density under regular wave conditions on a sandy beach and found that plastic particles were accumulated in shallow waters. (Stolle et al, 2019) studied the effect of bottom friction on transport of shipping containers under tsunami-like flow conditions, and found reduction of longitudinal displacement of containers due to the bottom friction. (Nistor et al, 2017) studied the displacement of multiple debris placed in a single row and found that their displacement was not influence by the number of debris, demonstrating lack of their interaction. (Goral et al, 2021) experimentally studies motion of spherical particles under breaking and non-breaking solitary waves. They also used slopes with different porosity in order to demonstrate how the slope material affects the debris transport.