Abstract:
Historic structures have a significant role in the social and cultural heritage of Kosovo. Many of the old monuments in Kosovo are mosques of Ottoman period, and the construction material used is mostly stone masonry. The majority of those mosques are still functional serving for religious purposes. Due to the aging of the structures, seismic activities, temperature changes, weather conditions, inappropriate maintenance, and lack of studies caused many structural deficiencies. In order to provide a fundamental understanding for the origin and impacts of structural defects, structural assessment of a related case should be done. Since it is required a representative model, Bajrakli Mosque located in western Kosovo is selected as a case study.
The first assessment of the study involves visual inspection of the structure for identifying cracks and other structural deficiencies. During the observations, many cracks are found in structural elements such as domes, pendentives, arches and load bearing walls. One of the causes of the cracks is the stress concentration of the critical regions of the structure.
For a better and detailed understanding of the structural deficiencies, finite element analysis is prepared in SAP2000 for Bajrakli Mosque. During the analysis, structural behavior of the undamaged model is observed through static and dynamic loads.
Finite element analysis provided important data on identifying the critical regions of the structure. The maximum displacement for load combination of self-weight and earthquake load is found in the middle dome and around the arches of the entrance hall with a value of 7.1 mm and 8.0 mm for X and Y direction respectively. Furthermore, the highest stress concentration values are found to be in the small domes of entrance hall, in the openings around the main domes and its connection with arches, and around the openings of the load bearing walls. The output values of the stresses in the roof system exceed the allowable limits defined in the study. The results provided by finite element analysis correspond to the findings from visual inspections.
