Seismic performance assessment of timber-framed (hımış) structures with different infill materials

This study investigates the seismic performance of traditional timber-framed (hımış) structures incorporating different types of infill materials through advanced nonlinear finite element modeling. Timber-infilled walls represent a widely used hybrid construction typology in seismic regions, where the interaction between the ductile timber frame and brittle infill materials critically influences structural behavior. Four configurations are analyzed: (1) Timber frame with adobe (mudbrick) infill; (2) Timber frame with fired clay brick infill; (3) Timber frame with natural rubble stone infill; and (4) Bare timber frame. A series of three-dimensional pushover analyses are conducted using ANSYS Workbench, where all materials are modeled using Multilinear Isotropic Hardening plasticity, including contact-based interface definitions and geometric nonlinearity. The mechanical behavior of each wall system is interpreted based on key seismic performance indicators, including initial lateral stiffness, base shear capacity, effective displacement ductility, and energy dissipation. Results show that while infill materials significantly increase the lateral strength and stiffness of the wall systems, they also introduce varying degrees of brittleness and reduced ductility. These findings emphasize the critical role of infill type in the seismic response of timber-framed walls and highlight the importance of understanding frame–infill interaction for the assessment and retrofitting of traditional building stock in earthquake-prone regions.