Seismic Vulnerability and Rehabilitation of One of the World’s Oldest Masonry Minaret under the Different Earthquake Frequency Content

Historical sites and remnant monuments from different eras in Iran are the main reasons of tourist attraction. One of the factors that endanger existence of these monuments is earthquakes and it is well known that Iran is located on the Alpide seismicbelt and earthquakes are inevitable. Understanding the structural behavior as well as possible weaknesses and then seismic strengthening under the earthquake are the ways of mitigating hazard in architectural heritage. Minaret of Tarikhanehmosque which is one of the oldest minarets and most precious historical monuments in Islamic world was built between 130 and 170 AH (750-760 AD). In the present study, this minaret is first modeled via ABAQUS finite element software considering geometric details and different seismic analysis such as pushover, modal and nonlinear time history analysis is conducted under the different earthquake frequency contents. After realizing the current state and weaknesses of the minaret, seismic strengthening is done via three different methods including FRP sheets, Ferro-cement (welded wire mesh with micro-concrete/mortar), and fiber reinforced cementitious matrix (FRCM) material. Finally, results of these three strengthening methods were evaluated and the most appropriate method was selected. According to the results, it was observed that Ferro-cement strengthening method is the most effective one among the proposed methods; so that, in comparison to the FRCM strengthening method, this method is effective by up to 100 %.