Dynamic Analysis of a Multistory Frame RC Building with and Without Floating Columns

This paper tends to evaluate the behavior of five- story RC building with and without floating columns using RC frames as lateral resisting system. This investigation had been carried-out using ETABS Ultimate V.18.1.1. The defined load cases, load combinations, the equivalent static lateral load pattern, and the response spectrum function were defined according ASCE7-16. The design criteria were set to be according to ACI 318-14. Eleven cases were proposed to investigate this behavior. One case was the building without floating columns. Nine cases were the building with different floating column schemes and the final case was the building with floating columns and another lateral resisting system (shear walls) for comparison purpose. Further comparisons of the results for all models are executed on the basis of parameters such as, story displacement, story drift, story stiffness, and response spectrum modal period. The results showed that, although the floating columns play an important role in architectural divisions or in multi-use buildings, but it affected the stiffness of the building negatively that led to increasing of the story lateral displacement and drift, also it led to increasing of modal time period. This mostly led to using a more stiffness lateral resisting system and eventually increasing the building’s structural costs.