Abstract
The structure of Tvrđa and its buildings date back to the Middle Ages. Tvrđa represents the Old Town of the city of Osijek and the best-preserved and largest ensemble of Baroque buildings in Croatia. After the withdrawal of the Ottomans in 1687, during the 18th century, the Austro-Hungarian administration systematically formed a new fortification system, regulated streets and squares and built a large number of military objects. Tvrđa took its present form in the 19th century and has kept it since then. Investigating the historical development of individual buildings, in addition to archival sources and existing architectural documentation, the obvious source of information are the buildings themselves. The aim of this paper is to explore the possibilities of using infrared thermography to find structural elements and hidden openings in historic buildings in Osijek’s Tvrđa. This paper describes the exploration of the 18th century openings on the facades of the former Kostić houses. The facades were bricked into the walls in the 19th century because houses were reused and their purposes changed from commercial to residential. Infrared thermography is often a starting, nondestructive testing method (NDT) for building analyses. This paper presents thermographic analyses of two buildings. The analyses were carried out in December 2017 and January 2018. Using a steady-state thermographic analysis of a building envelope as the first step, the audit was continued with step heating (SH) of an interest point where changes in a thermal pattern were expected due to additional bricking. Heat flux was generated by the usage of a heat gun for paint removal.
Highlights
Croatia, as a part of the Mediterranean zone of the Alpine-Himalayan seismic belt, is located in an area of high seismicity, as confirmed by earlier catastrophic earthquakes in Zagreb (1880)and Dubrovnik (1667)
The aim of this research is to explore the possibilities of using passive and active infrared thermography in detecting structural elements and hidden openings in historical buildings in the old city Tvrđa located in Osijek [3]
Thermograms were recorded with a FLIR E6 camera with a resolution of 160 × 120 pixels, field of view 45◦ × 34◦, temperature ranges from −20 ◦ C to 250 ◦ C, resolution difference of
Summary
As a part of the Mediterranean zone of the Alpine-Himalayan seismic belt, is located in an area of high seismicity, as confirmed by earlier catastrophic earthquakes in Zagreb (1880)and Dubrovnik (1667). As a part of the Mediterranean zone of the Alpine-Himalayan seismic belt, is located in an area of high seismicity, as confirmed by earlier catastrophic earthquakes in Zagreb (1880). Built from stone and masonry blocks, do not follow any provisions and are not in accordance with earthquake-resistant design. It is necessary to evaluate the level of seismic risk to these old buildings. Vulnerability assessments of the cultural heritage located in seismic areas has been actively researched [1,2]. In the papers by [1,2], the authors proposed a nondestructive and relatively fast but accurate seismic vulnerability assessment of heritage buildings in Tvrđa, the old core of Osijek city. Performing a detailed analytical design can be of great significance in order to validate this fast seismic vulnerability method. The factor that complicates seismic analysis is that heritage buildings are highly anisotropic and have complex
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
