Correlation between weather conditions, heating of structural elements, and the dynamic behavior of Mallorca Cathedral

Abstract

Mallorca Cathedral stands on ancient Roman and Islamic ruins of the city of Palma de Mallorca, on Mallorca Island (Spain) overlooking the Mediterranean Sea. The cathedral is an imposing structure, grand in design both inside and out, of significant cultural heritage. It has religious and historical importance for the island, thus its preservation has been the motivation of several studies into its structural behavior. An overview of Mallorca Cathedral is given in this thesis including a chronological construction history and description of the building, materials, and seismicity of the island. Thermography and dynamic monitoring, both used to collect data for the analysis, are also summarized in general as well as in relation to historical constructions. The analysis of the cathedral investigated the effects of the change in stone temperature and ambient meteorological conditions on its dynamic behavior. Data was collected over a two periods of two weeks in the winter and the summer of 2011 for the external weather conditions obtained from a public database, stone temperature by means of thermographic imaging, and modal frequencies by dynamic monitoring. A multiple linear regression analysis utilizing principle component was then performed on the compiled winter data to establish the relationship between the stone temperature and ten modal frequencies of the cathedral in the east-west and north-south directions. A brief wind analysis was done on the first modal frequency to determine if its presence was affected by wind direction and/or velocity. Results from the statistical analyses are presented in this work and concluding comments end the thesis along with recommendations for future study in this area.