George POTERAŞ, Mihaela Andreea MONCEA, Ana Maria PANAİT

Researches regarding Marine environment corrosion on coastal structures

The impact of the marine environment on the coastal structures was reported since the middle of the XIX century. In order to test the aggressiveness potential of the Black Sea water on the coastal constructions, between the years 2009 -2010, a seawater sampling program was carried out in the Navodari - Vama Veche sector of the Romanian coastline. Therefore, seawater samples were collected from 15 locations situated along the Black Sea coastline in order to determine their action o n coastal constructions. For all the samples the pH, electrical conductivity, salinity were determined in -situ and presented normal values. The aggressiveness of the seawater samples was determined in laboratory, through a parallel analysis of the SO 42- and Mg 2+ ions concentrations in seawater compositions. The results showed the presence of MgSO 4 in the analyzed samples, which affected the mortars used in determinations even after 3 months of storage. It was also observed that the only materials resistant to the water aggressiveness were the mortars with 20% dolomitic limeston e. Additionally, the investigation determined that the seawater aggressiveness affects not only the concrete structure but also has a great impact on the metallic parts found in these structures by highly corroding them, as seen for the Mamaia Bridge, build in 1935, the hydrotechnics nodes and other coastal structures.

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