The proposed PhD research titled “Seismic Fragility Assessment of Bracing Systems of Steel Buildings”
aims to investigate how the performance and fragility behavior of steel structures equipped with concentric
or eccentric bracing systems. Although infill walls are often treated as non-structural elements, their
interaction with the surrounding steel frame can significantly alter the stiffness, strength, and energy
dissipation capacity of buildings under seismic loading. This research seeks to quantify these effects through
detailed analytical modeling and probabilistic fragility assessment. The study will begin with a
comprehensive literature review to identify current gaps in understanding the interaction between infill walls
and bracing systems. Finite element models of multi-story steel frames with different configurations of
eccentric braces will be developed using advanced simulation tools such as SAP2000. Both bare frames and
infilled frames will be subjected to nonlinear static and dynamic analyses to capture their seismic responses.
Fragility curves will then be generated using incremental dynamic analysis (IDA) to assess the probability of
reaching various damage states under earthquake excitations.
Adjustments in research goals may include comparing different infill materials (e.g., masonry vs. concrete
blocks) or investigating retrofitting strategies to optimize performance. The expected outcome is to develop
refined fragility models and design recommendations that enhance the seismic resilience and sustainability
of steel buildings in earthquake-prone regions.