Measuring rock slope damage on rubble mound breakwater through digital photogrammetry

Abstract

In coastal engineering, laboratory research is the primary way to investigate wave–structure interaction. Different techniques can be used to study the stability of coastal structures and the related damage level, among which, the most consolidated one exploits the laser profiling system, with costly and time-consuming procedures. The present research proposes an innovative method, based on photogrammetry, for the measurement of the damage of rock slope structures (i.e. depth and extension of the damaged area). The approach has been tested and validated during an experimental campaign carried out on a 2D-physical scaled model of a rubble mound breakwater at the EUMER Laboratory (University of Salento, Lecce, Italy). Photogrammetric outputs have been compared with the laser derived profiles, under different structures layouts and hydrodynamic conditions. Results have proven to be highly accurate (relative error lower than 5%), with time and cost-effective equipment (standard digital camera) and simple acquisition and processing procedures.