HISTORIC CHIMNEY STACKS: SEISMIC ASSESSMENT AND KINEMATIC ANALYSIS

Many heritage buildings have chimney stacks of high architectural and cultural value. Most are built of brick or stone masonry, are often slender, and are prone to overturn even under slight quakes since undergoing great amplification of the seismic motion because of their position in the building. Notwithstanding thousands of chimney collapses during more or less recent earthquakes, causing considerable loss of cultural values and building damage, they remain one of the most disregarded nonstructural elements. This paper specifically addresses the analysis of the overturning mechanisms of chimney stacks to better know their vulnerability and provide a simple tool for their protection and conservation. The seismic behavior is studied through the displacement-based approach, considering the filtering effect due to the underneath building structure through floor response spectra. The main parameters influencing their seismic safety are also discussed. The procedure, applied to high chimney stacks of the Royal Palace of Carditello, built in 1787, is suitable for analyzing numerous historical masonry chimneys, to identify the most critical situations where it would be necessary to intervene in advance.