Finite element analysis and seismic rehabilitation of a 1000‐year‐old heritage listed tall masonry mosque: Fid-Bau Portal

Finite element analysis and seismic rehabilitation of a 1000‐year‐old heritage listed tall masonry mosque

Mortezaei, A. / Kheyroddin, A. / Ronagh, H. R.

Architectural heritage is not only culturally important but also economically vital as it is a great support for tourism and leisure industries bringing in billions of dollars to otherwise ailing economies of many older regions of the world. Protecting these often very heavy masonry structures in high seismic zones is a challenge that is of great concern for authorities, researchers and engineers alike. Post‐Islamic monumental buildings of Persia are among the world's most beautiful heritage listed architecture. Every large city in Iran has a mosque called ‘Masjed‐e‐Jam'e’ meaning the great mosque. This is the mosque in which the Friday prayer (a social must for Muslims) is often held. These mosques are large, always with tall minarets and often with a huge gathering area called ‘Ivan’ that are identifiable by their huge walls and dome or semi‐dome shaped roofs. The structure of the building and minarets is often made of bricks laid with lime mortar; and as such they are heavy elements most susceptible to earthquake's ground acceleration.

This paper presents the results of an analysis of the structural behaviour and seismic vulnerability of the ‘Masjed‐e‐Jame’ of Semnan, a heritage listed building dating back to 11th century AD. The analytical tool used here is a nonlinear static/dynamic finite element method. Using this tool and comparing demand versus capacity confirms the susceptibility of the building to extensive damage and possibility of collapse, as is frequently observed in this type of buildings. Another aspect of the study presented here has been the evaluation of the actual efficiency of current techniques of repair and strengthening of these structures. It is shown that usual structural reinforcement techniques are effective in providing increased seismic capacity. The paper advocates that significant information can be obtained from advanced numerical analysis, with respect to the understanding of existing damage and design of strengthening system. Copyright © 2010 John Wiley & Sons, Ltd.