Static and dynamic analysis of castellated frame systems

Castellated frames are defined as steel structures created using castellated beams and columns instead of traditional flat steel structural elements, with the aim of improving structural performance while reducing the weight of the structures without compromising their strength. In this study, two different frame models are analyzed, each with various web opening types, through static and dynamic analyses. The analyses are conducted using the finite element method in three dimensions with the ANSYS 2024 software. The frame elements, specifically the columns and beams, are modeled using the IPE200 section profile. The columns are evaluated in two different types (solid and with square web opening), while the beams are analyzed across five different web opening types (solid, circular, square, hexagonal, and octagonal), resulting in a total of 19 frame models. In the static analysis, four different loading conditions are considered, and a total of 76 models are solved to evaluate the total displacement, principal stresses, Von-Mises stress, and maximum shear stresses. In the dynamic analyses, both free vibration analysis and forced vibration analysis (undamped and damped) are performed. The free vibration analysis focused on the maximum displacement values for the first 10 modes, while the forced vibration analysis investigated the effects of damping ratios under horizontal and vertical dynamic loading. The results obtained from undamped and damped cases are compared, examining the impact of web opening types and column-beam combinations on the dynamic behavior of the castellated frame models. The analysis results revealed that the static and dynamic performances of castellated frame systems vary based on the web opening types of the beams and columns. Notably, the octagonal and hexagonal web openings led to significant differences in total displacement and stress values. Additionally, it was observed that increasing the structural damping ratio improved the performance of the frames under dynamic loading conditions.