DualSPHysics modelling to analyse the response of Tetrapods against solitary wave

The stability of Tetrapod armour units against solitary waves using Smoothed Particle Hydrodynamics (SPH) method is analysed in this work. To this purpose, the SPH-based DualSPHysics code was coupled with the multiphysics library Project Chrono. Tetrapod units are placed above a submerged mound. DualSPHysics solves the fluid-solid interaction, while Project Chrono solves the Tetrapod-mound interactions based on the contact and material properties of the block surface. The motion of the units during the simulation was compared with the physical model experiments where Tetrapods are made of mortar, and the mound is in PVC. The numerical results expressed as displacements of Tetrapods and damage ratio under different solitary waves are in reasonable agreement with the experiments, proving the capability of the DualSPHysics code to simulate challenging environments under the same numerical framework. The validated tool is then applied to study the stability for different coefficients of friction between mound and Tetrapods aiming at simulating the effects of different materials and surface roughness.