| 摘要 |
<p>Abstract The present invention relates to a non-combustible roofing system for construction comprising: a sloped or flat shear diaphragm supported on light gauge cold rolled metal framing, the shear diaphragm comprising a reinforced, lightweight, dimensionally stable cementitious panel and the framing comprising metal roofing elements; the cementitious panel having a density of 65 to 90 pounds per cubic foot and capable of resisting shear loads when fastened to framing and comprising a continuous phase resulting from the curing of an aqueous mixture comprising, on a dry basis, 49 to 68 weight % blend of reactive powders, 23 to 36.1 weight % uniformly distributed lightweight filler particles, and 5 to 20 weight % alkali-resistant glass fibers, and optional superplasticizer, the continuous phase being uniformly reinforced with the alkali-resistant glass fibers, and the lightweight filler particles comprising uniformly distributed ceramic microspheres, the lightweight filler particles having a particle specific gravity of from 0.02 to 1.00 and an average particle size of about 10 to 500 microns (micrometers), wherein the blend of reactive powders comprises:45 to 75 wt. % calcium sulfate alpha hemihydrate, 20 to 40 wt. % Portland cement, 0.2 to 3.5 wt. % lime, and 5 to 25 wt. % of an active pozzolan comprising silica fume; wherein the cementitious panel is attached to the metal roofing elements by screws to provide a shear load bearing roofing system, wherein the system has a horizontal design shear capacity of the roof shear diaphragm of 300 to 1000 pounds per linear foot, wherein the cementitious panel has a thickness of about 1/2 to 1 1/2 inches, wherein the screws are metal screws with winged drillers, the winged drillers located above the point and below the first threads of the screw and protruding laterally from a shaft of the screw. 2771339.2 (GHMalme) P72389.AU.1 "/'7</p> |
