Performance evaluation of steel-concrete composite structures designed in poorly graded soils

In this study, the seismic behavior of steel concrete composite buildings in a specific region was investigated. For this purpose, 5-, 10-, 15- and 20-storey composite moment-resisting framed structures were designed. Moment-resisting composite framed structures are modeled with concrete-filled steel tube columns and designed and modeled using composite beams. The buildings are designed according to cYTHYE-2016 and TBEC-2018 regulations at design levels with high ductility. In the design of the designed structures, the peak ground acceleration value is 0.79 g, and the design ground is planned as ZE class. SeismoStruct software was used for the design and performance evaluation of the structures. During the performance evaluations of the structures, nonlinear static pushover and incremental dynamic analyzes were used. Uniform and triangular load distributions are adopted in the static pushover analysis and 16 earthquake ground motions are used in the incremental dynamic analysis. Evaluation of the effect of the number of stories on the earthquake behavior of composite moment-resisting framed structures was investigated using the non-linear analyzes mentioned. Accordingly, lateral response, overstrength factors, ductility, and dynamic behavior factor values for composite frame structures were calculated and presented using the relevant analysis results. It has been calculated that the behavior factor of all moment-resisting composite framed structures can perform well above the design assumptions, whereas moment-resistant composite framed structures absorb seismic energy by using inelastic deformations. Ductility is almost 30% higher than the design assumption for international standards. As a result, it was concluded that these structures could continue to serve theoretically.