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A two-dimensional (2D) laboratory investigation on the horizontal and vertical hydrodynamic forces induced by tsunami-like solitary waves on horizontal circular cylinders placed on a rigid sea bed is presented. A series of 30 physical model tests was conducted in the wave channel of the University of Calabria in which a rigid circular cylinder was equipped with 12 pressure transducers placed along its external surface to determine the wave loads, with three wave gauges to record the surface elevation. The observed experimental range was characterized by the prevalence of the inertia component for the horizontal forces and of the lift component for the vertical ones. On the basis of the performance of several time-domain methods, the wave loads and the undisturbed velocity and acceleration derived from the surface elevation of the cylinder section were used to calculate the drag, lift, and horizontal and vertical inertia coefficients in the practical Morison and transverse semi-empirical equations.

Large-scale physical experiments (Froude scale, 1:4.3) were performed at the new Delta Flume in 2017, aimed at investigating wave impacts on a vertical wall placed on the top of a dike in a mild slope shallow foreshore. Experiments also allowed to investigate the morphological evolution of the sandy foreshore, the scour at the dike toe and its development under irregular and bi-chromatic wave conditions. Both experimental results and numerical study performed to design the experiments are reported. Moreover, preliminary validation of the model to investigate the scour within a wider range of wave conditions and foreshore slopes is illustrated.

This work deals with an experimental and numerical study on the horizontal and vertical hydrodynamic forces induced by tsunami-like waves on horizontal cylinders. The laboratory investigation has been performed in the wave flume of the University of Calabria. Twelve pressure transducers have been mounted along the external contour of a cylinder, while four wave gauges have been located close to the cylinder and an ultrasonic sensor behind the paddle to measure its displacement. Tests have been carried out for Keulegan-Carpenter numbers, KC, ranging from about 4 to 7. By the numerical viewpoint, a diffusive weakly-compressible SPH model has been adopted. To prevent spurious flows near the cylindrical contour, a packing algorithm has been applied before SPH simulations. The acoustic components occurring in the numerical pressure field have been filtered through the application of Wavelet Transform. By using different calibration methods, experimental and SPH forces and kinematics at the cylinder have been used to calculate the hydrodynamic coefficients in the Morison and transverse semi-empirical equations for engineering purposes.

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