Fire-induced changes in modal behavior and seismic implications for historical masonry mosques
Year: 2026
Type: article
Abstract: This study investigates the influence of fire on the dynamic behavior of historical masonry mosques and examines the seismic implications of fire-induced changes in modal characteristics. The Hacı Kasım Mosque in Trabzon, featuring stone masonry walls and timber interior elements, was selected as a representative case study. A hybrid analysis framework was employed, beginning with operational modal analysis (OMA) to obtain experimental data, followed by calibration of the finite element (FE) model using these results (with MAC > 0.89 for the first three modes). A two-hour fire scenario conforming to the ISO 834 standard was simulated, and the temperature distribution in critical regions was determined through transient heat transfer analyses in ANSYS. Temperature-dependent reductions in the modulus of elasticity were incorporated into the post-fire model using Eurocode 2 reduction factors, after which modal analyses were conducted. Comparative assessments revealed a 10–15% reduction in natural frequencies, up to a 60% decrease in mass participation ratios in higher modes, and the emergence of localized vibration modes concentrated in fire-affected regions, indicating that fire-induced stiffness degradation not only alters the global dynamic characteristics but also amplifies localized seismic vulnerability. These findings highlight that conventional post-fire restoration practices may be insufficient to ensure the safety of historical structures and emphasize the urgent need for performance-based conservation strategies.
Institutions: Erzurum Technical University, Ankara University
Language: English
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,990
Funder: Erzurum Teknik Üniversitesi
OpenAlex ID: W7130364510