Response of Little Hagia Sophia (Church of SS Sergius and Bacchus) to adjacent Train-induced Vibrations

Abstract

Cultural heritage structures have recently faced the adverse impacts of traffic-induced vibrations more frequently than ever due to rapid and excessive urbanization. Closeness of Little Hagia Sophia Mosque to the intense traffic of an adjacent railway line in İstanbul made it vulnerable to the long-term and repetitive action of ground vibrations. To understand the structural response of this Byzantine edifice, an extensive vibration measurement program was conducted on and around the structure. After the construction material properties were determined, a numerical model of the structure was created and modal, self-weight and time history analyses were applied. It was observed that the maximum stresses reach approximately 45% of the tensile strength of the construction materials at certain locations. Cyclic loading of traffic-induced vibrations can be a significant contributing factor in the gradual material deterioration along with other environmental factors. Furthermore, measured peak particle velocity at the gallery level of the structure critically exceeded the limit of 2.5mm/s for historic or sensitive structures.