Dynamic Behavior of a Suspended Steel Space Frame-Glass Composite Floor

This study investigates the dynamic performance of a large-span suspended steel space frame-glass composite floor (SSSF-GCF). Both the ambient vibration and the human-induced vibration of the floor were experimentally measured to identify vertical dynamic characteristics and evaluate vibration serviceability of the floor. Although vertical dynamic characteristics of the floor based on the global simplified finite element (FE) model of the structure agree well with those identified via experimental modal analysis, the global simplified FE model significantly underestimates vertical vibration amplitudes of the floor due to the coupled effect between two layers. Accordingly, an equivalent local FE model of the floor system was proposed and updated via adjusting the vertical stiffness of the interstory hanging pillars. It is shown that the equivalent local FE model can well predict both the dynamic characteristics and human-induced vibration response of the floor. Finally, the effect of the damping ratio on the acceleration response of the floor was numerically demonstrated with the verified local FE model.

Numerical Analysis Of Viscous Wall Dampers On Steel Frame

The structure is designed to minimize component damaged, one of them is using a damping system. Viscous Wall Damper is one of the damping systems, using high viscosity liquids as dampers. The viscous wall damper is represented by an Exponential Maxwell Damper model. Much of the literature shows the ability of viscous wall damper by experimental studies, but few of them had discussed numerically. This article will present an analytical model of the viscous wall damper, add viscous wall damper element to an existing frame and numerical analysis. The analysis was performed by a computer application on a steel space frame that excited a combination of three earthquake types. The influence of Viscous Wall Damper showed that a significant decrement of displacement u1 at the structure with Viscous Wall Damper in X & Y direction (50,78%) and with Viscous Wall Damper in Y direction (23,96%). The decrement displacement happened in all structure. At the end of the analysis shows the reduced of the structure periods, the structure response (displacement, velocity, and acceleration). All these results conclude that the structural components damaged due to loads can be greatly reduced.

Experimental Validation of Wave Vibration Analysis of Complex Vibrations in a Two-Story Metallic Space Frame Based on the Timoshenko Bending Theory

In a space frame, there exist in- and out-of-plane bending, axial, and torsional vibrations. The analysis of complex vibrations in such structures has relied mostly on numerical approaches. In this study, a wave-based analytical approach is applied to obtain solutions to vibrations in space frames. Both free and forced wave vibration responses are obtained, with bending vibrations modeled using the Timoshenko theory. A two-story steel space frame is built to validate the analytical results, and good agreements have been reached between the analytical and experimental studies. The effect of torsional rigidity adjustment on the accuracy of predicted vibrational responses in structures involving rotationally nonsymmetric cross sections is also examined.