Atmospheric corrosion seriously affects the working life of construction metals. The quantitative knowledge of the corrosion effects helps the maintenance and the materials’ logistics. In this work, in a military airport located by the sea, the corrosion damage equations of carbon steel, aluminum, zinc and copper are determined after outdoor exposure for four years. Exposure started in 2014, at two different periods of the year, in summer and in winter, for all cases. Weight loss measurements were performed as well as characterization of the exposed metal coupon surfaces by microscopy: optical, electron and atomic force, by X-ray diffraction and Fourier Transform Infrared Spectroscopy. Atmospheric conditions and pollutants were also evaluated. The derived corrosion equations of all tested metals for the exposure have been employed for the 30-year projection of expected corrosion. A parallel 12-month exposure of steel and aluminum—the most common airport metals—have been evaluated for five consequent years to designate the rating of the airport, according to ISO and ASTM Standards. The results showed that there is not a good correlation between the predictions of the Corrosion Damage Algorithm and the Europe Corrosion Map and the actual measurements on steel and aluminum at the site.

<p class="Abstract">Finite element analysis is employed to investigate the mechanical behaviour and failure scenarios of the marble block–steel clamp ancient masonry system utilised in the Parthenon (Athens Acropolis) under static loading analysis. The input data for the model are acquired by the laboratory testing of early 20th century restoration steel clamps, such as through tensile strength measurements and metallography, as well as bibliographic sources from various scientific fields (i.e. material properties, archaeometry, restoration, structural engineering and geology). Two different embedding materials (Portland cement mortar and lead), used for the nesting of the clamps, are examined under bending or stretching, induced by acceleration forces. The conservation status of the materials is taken into account by employing an intrinsic stress, as is the case when corrosion products build up in a confined space. The aim of this work is to provide a tool for the assessment of the conservation potential of the marble blocks in parts of the monument that require specific attention. Simulation results indicate the resilience of the Parthenon’s structural system under most examined scenarios and highlight the importance of intrinsic stresses, the existence of which may lead to the fracture of the marble blocks under otherwise harmless loading conditions.</p>

This work presents a corpus of measurement methodologies utilized during a multidisciplinary project, aiming at the protection and conservation of ancient steel joints (clamps and dowels) of the Acropolis monuments, undertaken by the Acropolis Restoration Service (YSMA). The Laboratory of Physical Chemistry of the National Technical University of Athens collaborated with YSMA in designing and evaluating laboratory scale and field experiments, aiming in testing conservation materials. The first phase involved the application of seven coating systems on uncorroded metal coupons. The application characteristics, physicochemical properties (colour, gloss, hydrophobicity), and the protection performance against accelerated corrosion and polymer photo-oxidation were measured. Poligen CE12 and Paraloid B67 +2% nano-alumina were selected as the two most suitable materials for pilot applications on corroded steel joints and outdoor field exposure at the monument site. The assessment of the two coatings reversibility and of the corroded surfaces chemical alteration was undertaken by Raman spectroscopy analyses and orthophotographic documentation. During the 1-year field exposure, the corrosion development was retarded, but some local events of active corrosion could not be prevented. The joint areas coated with Paraloid B67 enhanced with 2% nano-alumina enabled more uniform application on corroded surfaces and exhibited better corrosion protection. In case of Poligen CE12, the nature of corrosion products indicated local acceleration of corrosion reactions.

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