Interstitial seismic resistant support for an acoustic ceiling grid

摘要

Ceiling suspension system including a plurality of rigid, elongated seismic joists interposed between opposing walls of a room, spaced selected distances apart along a horizontal support plane, and hangers suspended from the respective joists to support a grid from the respective lower ends thereof.

主权项

1. A seismic vertical support suspension apparatus to suspend a ceiling grid between a first wall and a second wall that is parallel to and spaced a distance apart from the first wall comprising:
a suspension system interposed between the first wall and the second wall and including a pair of tracks supported from the respective confronting surfaces of the first wall and the second wall and opening inwardly toward one another; a plurality of transversely projecting metal seismic joists spaced apart along the tracks and constructed of a respective hollow tubular steel beams having overall transverse dimensions in at least one direction of at least 3⅝ inches; a plurality of hangers each of which comprises a metal hanger bracket with a rigid vertical-steel angles projecting downwardly from the metal hanger bracket, and having a lower extremity; wherein the metal hanger brackets, having respective interiors and exteriors, said respective exteriors abutting one side of the upper extremities of the respective rigid vertical steel angles and the respective interiors of the metal hanger brackets defining square bites that are configured to engage in close fit relationship over the top and bottom sides of each of the respective metal seismic joists; wherein said metal hanger brackets are rigidly carried from the respective seismic joists and each of the downwardly projecting rigid vertical-steel angles acts as a lever arm and is connected to the ceiling grid; wherein each of the metal hanger brackets and seismic joists cooperate in positively holding the respective hangers against rotation about their respective joists; and wherein the pair of tracks, each of the plurality of transversely projecting metal seismic joists, and each of the plurality of hangers cooperate to, in the case of a seismic event, positively resist movement of the ceiling grid relative to the first wall and the second wall.