Aspetti geotecnici e marittimi di due interventi di difesa costiera

Two case-histories of the design of submerged breakwaters for coast protection are shortly reported in the paper. The first one refers to the stabilisation and protection works of the sand beach of S.Alessio Siculo village, in Sicily, that suffered severe erosion triggered, some forty years ago, by the construction along the shoreline of a vertical seawall in lieu of the pre-existing sand-dune system. As a consequence, long stretches of the seawall were undermined and collapsed, and the beach almost disappeared. A submerged breakwater was built to reduce the inten-sity of wave attack, the seawall was rebuilt where necessary and provided with a rock revetment at the toe, and then a “perched”…