| dc.description.abstract | Stave church is a term derived from the technique of constructing a church using corner posts or staves as loading-bearing pillars. Currently there are only 28 stave churches in Norway, but in the mediaeval period over 1,000 of these churches were thought to have existed. Since early Christianity, the architectural design of these churches has undergone significant change. Consequently, the original structure of all remaining stave churches has been altered to some degree or another, with some of the churches being so extensively modified that it is nearly impossible to determine its original construction. Further, stave churches are not only known for their wooden structure, but also for their elaborate distemper polychrome walls which were once painted throughout the interior. Like the church’s structure, these wall paintings have been altered throughout the centuries; in several of the stave churches, the decorative wall paintings were washed away, removed or even overpainted, depending on what was perceived as being fashionable. And to-date, only two-thirds of the remaining stave churches still display a decorative interior. These structural and decorative alterations are unsurprising as the cultural significance of these architectural masterpieces has changed over time, and so have preservation and conservation methods and theories.
Stave churches are amongst some of the most important cultural heritage sites in Norway and preserving their structure and interior paintings is essential. However, providing an evidence-base that links properties of historic materials with the long-term effect of active interventions can be quite challenging, due to both the inherent complexity of the materials and uncertainty in the mechanisms at play. Although, scientific examination of artists’ materials, and how the properties are further influenced by exposure to conservation treatments, can assist in establishing a preventive campaign. Furthermore, chemical characterization of distemper paintings (i.e., pigments bound in a proteinaceous adhesive) is vital for deconstructing the artists’ palette and understanding the current preservation state of Norwegian stave churches. Moreover, investigating the mechanical behaviour of these paintings is critical for developing a comprehensive understanding of their long-term stability.
Hence, investigations within this thesis focused on the chemical and mechanical properties of historic polychrome paint samples taken from two Norwegian stave churches: Heddal and Eidsborg. With the aim of developing a deeper comprehension and awareness of these materials which can help to facilitate a better understanding of the current preservation state of the stave churches, and ultimately developing a more effective environmental risk management plan. Characterization of these historic materials was performed using various techniques. Whereas the inorganic and organic components of the historic paint samples were obtained using a multi analytical approach consisting of scanning electron microscopy (SEM), optical microscopy (OP), Fourier-transform infrared (FTIR) spectroscopy, x-ray diffraction (XRD), enzyme-linked immunosorbent assay (ELISA), and gas chromatography-mass spectrometry (GC-MS) after derivatization. The physical behaviour and microstructure of paint specimens was investigated using dynamic vapour sorption (DVS) and X-ray microtomography (micro-CT), respectively, while the mechanical properties were investigated using nanoindentation. Additionally, as the binding medium of paint influences its overall mechanical properties, nanoindentation tests were performed on different proteinaceous adhesives. Here, focus was given to commercial adhesives which are typically used by artists as well as those used for conservation treatments. | en_US |
