Infrared thermography and geophysical techniques in cultural heritage conservation

Abstract

Infrared thermography is a powerful tool of nondestructive evaluation, but it has some limitations when dealing with deep and low thermal resistance defects. This is the case of thick walls of historic buildings and buried anthropic remains, which are important tasks of the cultural heritage field. Thus, it is evident the need of relatively high-depth inspection techniques such as the geophysical ones. The main purpose of this study was to characterize the overlapping zone from low-to-high depth with infrared thermography and geophysical methods. The investigation was carried out on two-component structures including a plaster layer over a support of marble, brick, or tuff with plaster detachments intentionally created. Results prove that an integrated use of the two techniques allows for detailed evaluation of architectonic structures and provides information about the related causes of degradation

Influence of concrete properties on the detection of voids with impulse-thermography

“…During the last years, impulse-thermography has proven to be one of the best suited non-destructive testing methods to detect defects up to a depth of 10 cm [1][2][3][4][5]. The only precondition for detection is that these defects lead to a sufficient variation of thermal properties compared to the bulk material.…”

Infrared thermography of masonry structures

“…The distance of the lamp from the specimen surface D L was varied between 50 cm and 150 cm depending on the extension of the viewed zone, and, in turn, the heating duration t H was varied from 500 s up to 2000 s depending on the lamp distance and the defects depth. In any case, the combination of D L and t H was chosen to rise the surface temperature T s enough above the ambient temperature T a for good defects visibility [5,11]; this, for the tested conditions, was achieved with T s À T a in the range 2-5°C.…”

“…Infrared thermography can be used in civil engineering [1][2][3][4] to discover defects in buildings envelope, to monitor reinforcing steel in concrete, to detect moisture inside building walls, and so forth. It is known that IRT has some limitations when dealing with deep and low thermal resistance defects, but it has proved to be still useful in conjunction with high-depth techniques [5].…”

Infrared Thermography for the Characterization of Painted Vaults of Historic Masonry Buildings

“…In these cases, in fact, the execution of direct inspections and testing is usually not compatible with the needs to preserve the historical and artistic values inherent to painted ceilings or remarkable floors. Despite their limitations (Carlomagno et al, 2005), Nondestructive Testing (NDT) methodologies have lately gained increasing interest in this research field (Binda and Saisi, 2009;Grinzato et al, 2002), also thanks to the continuous improvement of technologies characterized by a low impact on the structures.…”