Shake table tests of a special raised floor system

Raised floors are commonly utilized in data centers to provide free space for heavy cable nets of servers. Different types of raised floor systems have large range of earthquake performance. In this study, the earthquake performance of a special raised floor system with altitude adjustment bolts is evaluated by the shaking table tests. The system consists of columns, primary and secondary beams made of steel box sections and special floor tiles. The level of the primary beams can be adjusted by the special screw system. The system was supported by RC foundation fixed to the shake table. The fully loaded data storage cabinets were connected to the secondary beams. The shake table tests were executed in two perpendicular directions namely parallel and perpendicular to the primary beams. The acceleration record of BOL090 (Duzce_Turkey 1999 Bolu) was scaled according to AC-156. The record was applied in the incremental form. Various displacement and acceleration components were recorded by means of the measuring system. The system displayed good performance in the two directions. The maximum relative drift obtained in the design earthquake is 1.9%. It has not been experienced high acceleration amplification on the raised floor.