## 7 Seismic Performance of Composite Building Structures
### Seismic Performance of Composite Buildings: State-of-the-Art
The modeling method was validated by comparing it with the experimental results. The examined composite structures satisfied the strong columns, weak beams principle. The impact of several characteristics, such as ductility, hysteretic curves, skeleton curves, energy dissipation capabilities, and stiffness degradation, on seismic behaviors was investigated. [PERSON] et al. (2023) [99] found that slip-permitted and uplift-restricted connectors significantly enhanced the anti-cracking capabilities of reinforced concrete slabs. They used numerical analysis and a sophisticated finite element model to analyze the seismic performance of steel-concrete composite frames using these connectors. However, the lack of research has limited their applicability in composite frames. The study emphasized how crucial design elements are for maintaining structural integrity during seismic events, including steel beam height, flange thickness, and connector arrangement length. Furthermore, [PERSON] et al. (2024) [100] proposed a composite frame with a high-strength steel-plate wall core tube resilient structural system as a new high-performance structural system. It is composed of a core tube with composite frames, interchangeable energy-dissipation coupling beams, and double steel-plate-concrete composite shear walls. They showed how the benefits of this novel system include decreased wall thickness, greater space utilization, enhanced control over the drift ratio, less damage and stiffness degradation, and higher seismic resistance to safeguard people and property. Taking into account the impact of floor loads, [PERSON] et al. (2020) [101] examined the seismic behavior of steel-concrete composite frames with large floor slabs. Three load cases were tested on a two-story, two-bay composite frame: pushover, longitudinal cyclic loading, and vertical floor loading. They examined strain distribution, mid-span deflection, and the emergence of cracks in the floor slabs. They also covered force processes of the composite frame, strength and stiffness degradation, load-displacement curves, energy dissipation capacity, and failure events. They also showed that fractures in the welds close to the external joint and the shear lag effect in the wide floor slabs affected the deformation pattern and force mechanism of the composite frame. Additionally, in order to evaluate the seismic risk and calculate the financial damages, [PERSON] et al. (2018) [102] examined the seismic demand of a steel-concrete composite structure utilizing a high-strength steel moment-resistant frame. Due to the intricate design of the building, a thorough 3D probabilistic seismic demand study that took the angle of the earthquake into account was necessary. Mild steel beams and round, high-strength steel columns filled with concrete made up the construction. There were several incremental dynamic analyses and nonlinear 3D FE models. Taking into account a variety of factors and the randomness of the impact angle, seismic fragility functions were constructed for damage and collapse  
Figure 7: Dynamic inelastic analysis results showing maximum inter-storey drift ratios for a 10-storey composite structure under seismic loading conditions (adapted from [PERSON] et al. (2021) [96]). limit states. The significance of peak ground displacement in the probabilistic model was demonstrated by the results. [PERSON] et al. (2015) [103] discussed the results of a performance analysis on various case studies, which are included in a final project report of a research project entitled OPUS. The seismic performance of the structures was assessed using 2D nonlinear models, and the structural behavior and collapse modalities were determined using pushover analysis and incremental dynamic analysis. The study also used the incremental dynamic analysis technique to identify the level of peak ground acceleration that activates collapse, and the Ballio-Setti procedure was modified to account for frequency discrepancies. This allowed for a comparison of the actual q-factor with the design standards.