Author(s): Vanessa Ferraz; Rita F. Carvalho; Jorge Leandro; Rute Lemos; Juana Fortes
Linked Author(s): Juana Fortes
Keywords: Rubble-mound breakwater; Armour unit motion; Wave incident; Image analysis; Matlab®
Abstract: Rubble-mound breakwaters often need regular upgrading and maintenance during lifetime. Scale model tests are many times required to evaluate hydraulic and structural behaviour of the proposed design. Stability and overtopping of breakwaters are examples where physical model tests are often chosen. Nevertheless, damage assessment depends often of a trained technician in order to properly identify motion and removed armour units (natural or artificial blocks) from the armour layer. In this work, we develop an image-based method using Matlab®to identify and characterize breakwater armour units motion induced by irregular waves during scale model tests. Different methodologies were tested and compared using three different types of armour units. With a proposed methodology of image analysis, it was possible to make an accurate monitoring of the structure during the entire test, to identify motions, to locate them in space and time, and to characterize the selected motion by calculating displacement and rotation.