Influence of Geometric Ratios on the Structural Behaviour of Historic Timber Roof Structures

Heritage buildings and historic structures are highly complex systems that have to be understood by performing multi-, inter-, and transdisciplinary studies. It is therefore important to understand how structural parts influence each other and how individual structural elements and their position affect the general behaviour of the whole system. Recent studies concerning roof structures have highlighted that there is a close link between all structural elements, not only from a load-bearing point of view but also from a geometric point of view. Therefore, it was observed that the general shape of the roof and the position of the main structural elements were defined by complex geometric ratios. Starting from this observation, the study is aimed at evaluating how important these geometric ratios are in the structural behaviour of historic timber roof structures from the 18th, 19th and 20th century from Timisoara. To evaluate their importance, numerical simulations were performed on the main frames of the selected case studies with original geometric ratios and altered ratios and their behaviour was compared in terms of displacements in key areas of the structure. The main scope of the study is therefore to highlight whether the presence of pure geometric ratios improves the structural behaviour of the considered roof structures or if these principles are only related to the general aesthetics of the roof structure.