Abstract:
Breakwaters are built to promote sheltered areas, for people, ships, and harbour activities. In the design of
rubble-mound breakwaters, a common type of breakwater in many countries, including Portugal, it is assumed
that damage may occur in certain stretches of the structures, and therefore maintenance and repair works will
be quite certainly needed. To successfully carry out these interventions, in a timely and cost-effective manner,
the structures must be observed and monitored systematically. This enables one to follow their structural
behaviour and, through diagnosis analysis, to specify the most suitable timespan to undertake any necessary
intervention. The severity of the sea on the Portuguese coasts justified the establishment, by the National
Laboratory for Civil Engineering (LNEC), of a program of Systematic Observation of Maritime Works
(OSOM) which, in 2018, was improved with the introduction of drones to monitor the structural present
condition, evolution condition and risk condition of the structures, namely movements and falls of blocks in
the armour layers. This communication presents some results of the application of OSOM+ program on
breakwaters in Sines and Algarve (Faro-Olhão and Portimão) harbours, an activity that LNEC has developed
for the APS – Ports of Sines and the Algarve Authority
