Abstract: An expansion joint for a parking structure includes first and second rails for mounting on adjacent slabs at opposite sides of a gap therebetween and a cover plate that overlies the rails and covers the gap while permitting relative movement between the slabs. A series of turnbars are pivotally coupled to the underside of the cover plate using ball and socket joints so that lateral loads imposed on the cover plate are transmitted directly into the turnbars, minimizing the risk of shear failure between the cover plate and the turnbars. At the same time, the ball and socket joints allow the cover plate and turnbars to tip with respect to one another. The turnbars have spherical end portions that are received in complimentary channels in the respective rails so that the turnbars maintain the cover plate centered over the gap.

Abstract: A drop-out fire vent for a building has a plastic dome that softens and loses structural integrity with increasing temperature. However, the dome is prevented from dropping out by an internal trap door controlled by a fusible link that will release at a precise temperature. This allows the vent to be used in combination with sprinkler systems such as ESFR systems that require opening of the vent at a precise temperature after the sprinklers have been triggered.

Abstract: A pressure relief panel assembly for protecting a building against over-pressure caused by explosion. The assembly has a panel pivotally connected to a frame and held by a calibrated magnet and striker set which releases when a predetermined over-pressure occurs. A cable restraint attached to a shock absorber, or a linkage of two arms attached to a shock absorber, limits the extent to which the panel can blow open. A spring mounted on one of the arms catches the other arm when the panel has blown open, preventing the panels from reclosing and thereby preventing implosion damage to the building. Alternatively, or additionally, the panel, after opening, may be held partly open by a stop bar which pivots to prevent the panel from fully closing, to prevent implosion damage to the building after the explosion.

Abstract: A pressure relief panel assembly for protecting a building against over-pressure caused by explosion. The assembly has a panel pivotally connected to a frame and held by a calibrated magnet and striker set which releases when a predetermined over-pressure occurs. A cable restraint attached to a shock absorber, or a linkage of two arms attached to a shock absorber, limits the extent to which the panel can blow open. A spring mounted on one of the arms catches the other arm when the panel has blown open, preventing the panels from reclosing and thereby preventing implosion damage to the building. Alternatively, or additionally, the panel, after opening, may be held partly open by a stop bar which pivots to prevent the panel from fully closing, to prevent implosion damage to the building after the explosion.