Operating conditions of unconventional rib and membrane shells

The paper presents some problems connected with a working construction of covers on sacred buildings in the form of wooden shells and metal sheets working together. The authors have carried out a scientific assessment of the technical state of wooden structural elements taking into account chemical and biological processes occurring in the structures. It was shown that the stress state manifested in the deformed shells was hazardous in character. A conception of investigations to analyze the technical state of the wooden shells was formulated so as to be able to define the pre-emergency state and also to carry out maintenance jobs to ensure long term, safe operation of the historical buildings of religious character.