Shaking Table Tests of the Cable Tray System in Nuclear Power Plants: Fid-Bau Portal

Shaking Table Tests of the Cable Tray System in Nuclear Power Plants

Huang, Baofeng / Lu, Wensheng / Mosalam, Khalid M.

Two series of shaking table tests were performed to investigate the seismic performance and damping ratio of the cable tray system in nuclear power plants. The required response spectrum of compatible floor-motion time histories was generated as the input motions to the shaking table. The full cable tray (100% loading) behaved elastically in the five operating basis earthquakes, and 1.5 times of safety shutdown earthquake (1.5SSE) excitations, while buckling damage occurred at the bottom of the column in the 2.0SSE. The experimental component acceleration amplification (CAA) factor is larger than that given by current codes. To determine the relationships between the loading ratio and both damping ratio and fundamental frequency, the cable tray was excited through the shaking table with white noise that has peak accelerations ranging from 0.1 to $1.0 g$ . The results show that the observed damping ratios are smaller than those specified in code provisions. This study shows that shaking table tests should be conducted to define a more-reliable damping value for the cable trays in nuclear power plants. Finally, a preliminary fragility analysis was conducted using the CAA factor as the indicator.