PSI - Issue 81

Mykhailo Hud et al. / Procedia Structural Integrity 81 (2026) 486–492

492

4. Conclusions The analysis shows that the asymmetric layout has a noticeable effect on the dynamic behavior of a multi-storey frame building. The base model, characterized by a regular and symmetrical layout, exhibits the lowest natural frequencies, reaching 4.53 Hz. According to the combined graph, this model belongs to the "flexible" category, characterized by increased sensitivity to vibrations. The presence of openings in the floors and asymmetrically located balconies contributes to increasing the stiffness of the system. It was found that the models with one or two openings, as well as the version with a balcony, exhibit high natural frequencies - up to 12.8 Hz - which classifies them as "rigid". Despite the geometric differences, the mid- and high-frequency components of their spectra are almost indistinguishable, indicating that local changes in the upper frame have a minimal effect on the mode shapes, given the dominance of the overall spatial structure. It is clear that an important observation is the aggregation of higher frequency modes within a limited spectrum. This finding serves to confirm the stability of stiffness and uniform operation of the modified models in contrast to the baseline. References Chopra, A. K., 2017. Dynamics of Structures: Theory and Applications to Earthquake Engineering (5th ed.). Pearson. Clough, R. W., Penzien, J., 1995. Dynamics of structures, Third Edition. Computers & Structures Inc., Berkeley, CA, USA. Hud, M., Ihnatieva, V., Baran, D., 2024. Influence of mass distribution on natural vibrations of a reinforced concrete building frame. Procedia Structural Integrity 59, 692 - 696. Hud, M., Chornomaz, N., Grytseliak, R., Baran, D., 2022. Study of the joint work of the foundations and the spatial tower under the action of dynamic loads, Procedia Structural Integrity 36,87 - 91. Paz, M., Kim,Y. H., 2019. Structural Dynamics: Theory and Computation. Springer. Iasnii, V., Yasniy, O., Homon, S., Budz, V., Yasniy, P., 2023. Capabilities of self - centering damping device based on pseudoelastic NiTi wires. Engineering Structures 278, 115556.