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In this experimental campaign, concrete‐to‐concrete interfaces were examined under cyclic actions, crossed by postinstalled reinforcing bars or industrial steel screws. In addition, the effect of the embedment length and the roughness was investigated. It was observed that different failure modes occur, depending on the different connector types and embedment depths. The positive effect of roughness on the interface resistance was confirmed, but the results indicate that, for very high roughness values, the resistance may be smaller than for moderate values. It was also noticed that the behavior of interfaces crossed by mechanical anchors was less stiff in the ascending branch and exhibited a less steep falling branch. The extension of the project on testing thin overlays showed that the resistance was significantly affected in case of cyclic loading, suggesting that the use of any type of anchor in seismic conditions needs to be supported by adequate experimental evidence.

This study aims at the acquisition of a reliable image of the nonvisible parts of historical masonry buildings in Greece by in-situ application of non-destructive techniques (NDTs). To serve the purpose of obtaining overall conclusions on the documentation of the monuments' internal condition, the deriving results are examined and combined together with the in-situ observations. The structures under investigation are the Katholikon of Osios Loucas Monastery (Boeteia), the Monastery of Kaisariani (Attica), the Agia Paraskevi Church (Chalkida) and the Nativity of Christ's Church (Athens). The main investigation method applied on all monuments was that of the Ground Penetrating Radar. Additionally, the methods of Boroscopy and Schmidt Hammer Testing were also used when further investigation was required. The techniques were applied on targeted areas, representative for the entire examined structure. Thanks to the assessment of the results, it was possible to identify data relevant to the dimensions and the type of stones used in the piers and the three-leaf masonries, the thickness and the condition of the mortar and the infill, the coexistence of different construction types in a structure, as well as the approximate compressive strength of stones.