Experimental investigations on two traditional minarets in Bosnia and Herzegovina

The paper is focused on the experimental investigations performed on tall, slender masonry structures (minarets) in Bosnia-Herzegovina by means of the application of on-site non-destructive tests. Traditional stone masonry minarets in Bosnia-Herzegovina were built firstly starting from the Ottoman period (from 15th to19th c.) and, as part of their corresponding mosque-building complex, are designated national monuments. The objective of the study is the definition of a clear knowledge-based procedure applied to historic masonry structure. The final aim is the assessment of the structural capacity of this kind of structures (in terms of strength, stability) subjected to earthquake-induced actions. In order to achieve the foreseen results, the first step in the knowledge process was the implementation of selected non-destructive tests (NDT): (i) dynamic testing to identify the global dynamic response and calibrate FE models; (ii) sonic pulse velocity tests to identify the morphology and quality of multi-leaf walls at the base of the minarets; (iii) IR thermography to evaluate the bonding of CFRP strips applied along the inner shaft of one minaret. The paper reports the results of the extensive investigation campaign performed by the authors on two structures: the minaret of the Hadži-Alija’s mosque in Počitelj and the minaret of the Koski Mehmed-Pasha’s mosque in Mostar. Particular attention is given to the identification of the dynamic properties of the two buildings, crucial for the calibration of advanced FE non-linear models. The outcomes of the experimental tests combined with FE results will be extended in a future research to a database of more then 20 minarets implementing on purpose parametric analyses.