Model updating of Masonry courtyard walls of the historical Isabey mosque using ambient vibration measurements

Abstract

Growing interest in the preservation of architectural heritage has revealed a need for tools that are capable to reliably analyze masonry structures. For decades, finite element modeling approach has been commonly used in engineering society to simulate these structures under different conditions; but most of the time, the responses obtained from experiments differ from those of simulations due to the complexity in inherent physical aspects such as material properties, boundary conditions, mass and/or stiffness uncertainties. From this perspective, model updating techniques have the potential to overcome these inaccuracies and become essential tools in developing verified finite element models compatible with experiments. In this paper, sensitivity-based finite element model updating studies of the courtyard walls of the historical Isabey Mosque located in Selcuk/Izmir are presented. Dynamic characteristics of the structure are estimated from two sets of ambient vibration measurements by the EFDD operational modal analysis technique. The initial numerical model of the courtyard walls is constituted by macro modeling strategy. In order to obtain a much better correlation with in situ tests, the uncertain parameters such as mass density, Young’s modulus, and boundary conditions of the initial numerical model are updated. Thus, a reliable finite element model that is more representative than the initial one is obtained to be used in future numerical assessment studies. In the presented paper, it is highlighted that the boundary conditions are often the most uncertain parts of a structural system, so they should be included in the updating process for realistic updating results.