Floor Vibration Experiment and Serviceability Test of iFLASH System

Abstract

Studies on novel composite structures that can decrease floor height and improve constructional efficiency in order to increase spatial efficiency and lease revenue have been actively conducted. An innovative fire-proof, lightweight, absorbed, shallow, and hybrid (iFLASH) system was developed to solve construction site issues, such as improving constructability, reducing construction time, and attaining structural efficiency by reducing the weight of the building structure. This system can shorten the construction duration and decrease the floor height and structural weight, owing to features such as a low thickness and light weight. However, studies on the vibration characteristics of this new floor system have not been performed yet. As the general thickness of the iFLASH system ranges from 25 to 30 mm, it must have a sufficient floor vibration performance in order to be utilized. To evaluate the floor vibration performance of the iFLASH system, an experiment was performed in two buildings where the system was applied. This paper presents the results of the dynamic characteristics and serviceability testing as basic data for the vibration characteristics of the iFLASH system.

Seismic Performance of F3D Free-Form Structures Using Small-Scale Shaking Table Tests

“…For free vibration, the initial displacement (8 mm) was applied to the test specimens. For sinusoidal forced vibration, the vibration with various frequencies ranging approximately from 0.7f to 1.2f was applied with constant amplitude and period during 30 s. From the free vibration, the damping ratios of the test specimens were obtained and the natural frequencies were also obtained from the sinusoidal forced vibration with constant amplitude and period [33,34]. In addition, sinusoidal force vibration with a specific frequency and designed peak acceler-ation by an earthquake was applied to the small-scale specimens to measure the dynamic behavior compared to finite element analysis.…”

“…And the only test results of the small-scale model for 10 s are shown in Figure 8, as test data after 10 s was negligible. The damping ratio can be obtained from the time history curve of the free vibration test using the logarithmic decrement method [33,35]. The logarithmic decrement method is to calculate the damping ratio (ξ) with reduction peak amplitude (u) for j cycles (Figure 9) under free vibration as follows: The damping ratio can be obtained from the time history curve of the free vibration test using the logarithmic decrement method [33,35].…”

Fire Resistance Performance of Steel–Polymer Prefabricated Composite Floors Using Standard Fire Tests

“…Recently, steel–polymer composite floors, which have a steel–polymer–steel sandwich-type section ( Figure 1 ), have been developed for application in steel structures as prefabricated floor members to reduce the construction period and improve construction efficiency [ 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ]. The thickness of steel–polymer prefabricated composite floors typically ranges from 25 mm to 80 mm.…”

“…Despite their shallow thickness, these composite floors show an equivalent flexural capacity to that of composite deck slabs [ 16 ]. In addition, the vibration performance of composite floors has been investigated, with the results indicating that they could be installed in residential buildings given the energy absorption of the polymers [ 17 ]. Considering the shear deformation of polymers between steel plates, a new approach was proposed for estimating floor vibration performance with improved accuracy [ 18 ].…”

Body CoM Acceleration for Rapid Analysis of Gait Variability and Pedestrian Effects on Structures

“…From a structural point of view, special attention may be required by pedestrian systems which can be more sensitive to walk-induced effects compared to other structural typologies. Traditional vibration serviceability assessment is based on consolidated structural health monitoring procedures and techniques [4][5][6][7][8][9]. Recently, various studies have started to assess the dynamic behaviour of laminated glass slabs under pedestrians, showing that structural dynamic parameters and performance indicators are rather different from other constructional solutions, as a major effect of flexibility, slenderness and (often) limited mass, compared to occupants [10][11][12][13].…”