investigation on novel connection in vertically mixed structures under lateral and axial loads

Abstract

Vertically-mixed structures are buildings constructed with different materials progressing in the vertical direction. These buildings feature a concrete frame on the lower stories but a steel one on top. Reinforced Concrete (RC) column connected to steel column in story that called transition story. The sudden change of stiffness in the transition story in these structures and the mass irregularity prompted research attempts concerning the response modification factor and the analytical period of the structures. There isn’t much research on this issue. Due to below concrete column dimensions upper steel column dimension is limited. To accurately study the transfer of loads, the stiffness of the transition story column, and its failure and seismic behavior, this study investigates full-scale experimental a test specimen under axial and lateral cyclic load. Proposed connection in this study that called trough bolt lap connection had good behavior in seismic load up to 4% drift ratio. No sign of failure and stiffness reduction observed in test results. Analytical finite element study is done for verification and parametric study in transition story column in variable axial load and longitudinal bars ratio to grass section of concrete. Studies have shown no failure in the column connection. Column had force-control behavior in lateral loads.

Keywords

• vertically mixed structures
• column connection
• transition story
• experimental study
• finite element