A Seismic Behavior and Rehabilitation of the Historic Masonry Minaret by Experimental and Numerical Methods

Historical masonry structures frequently present an unsatisfactory behavior under exerted seismic loads.Because ofcultural values and vulnerability of these kinds of structures to seismic loads, they must be protected and retrofitted in a way which is both safe and non-destructive. In this paper, Zein-o-din minaret, one of the Iranian historical structures in Kashan built in13th century was selected in order to find a solution which can be applied to other similar historic towers. First, some information on the geometric characteristics of the minaret was collected and afterwards by conducting related experiments, the mechanical properties of the materials were determined. Then, using ambient vibration testing, the structural dynamic behavior such as the main natural frequency of the minaret was obtained. Dynamic analyses of this minaret were implemented through ABAQUS software and the resulted natural frequency from the numerical analysis was compared to the corresponding value from ambient vibration testing. Finally, by utilizing the verified numerical models, various options were proposed for rehabilitation of the Zein-o-din minaret. The outcomes illustrated that using high strength grout for filling the gaps between the bricks and seams would be the best solution for renovation of this historical minaret.