The seismic performance of a cable tray system depends just as much on the building connection as on the tray itself. Every hanger, trapeze, beam clamp, concrete insert, and post-installed anchor should be reviewed for the seismic forces expected at that attachment. In regions prone to seismic activity, ensuring that your cable tray system is capable of withstanding such events is vital. This article will explore the importance of seismic resistance in cable trays, discuss when seismic braces are necessary, and help you understand how to make informed. A number of shake table tests on portions of cable tray and conduit systems confirm these observations from past earthquakes and demonstrate that typical configurations perform well under repeated high- level seismic input test spectra on the order of 1. During an earthquake, cable trays are exposed not only to gravity loads and normal service loads, but also to lateral movement, vertical acceleration, vibration, and building drift. Engineers typically use seismic design codes and standards to determine the appropriate design.
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