Behavior of Laminated and Filmed Glass in Severe Windstorm Environments

摘要

The research addresses the behavior of heat strengthened laminated glass underconditions which represent a severe windstorm. Specimens laminated with two different interlayers were examined. The interlayers were polyvinyl butyral (PVB) 0.060 in. in thickness and a sandwich combination of PVB and polyethylene terephthalate (PET) 0.033 in. in thickness. Glass specimens were tested in three glazing configurations, one 'dry glazed' and two with a silicone 'anchor bead'. The glass specimens were properly glazed into aluminum frames. The frames were then mounted onto a testing table creating an airtight chamber. The chamber enabled pressurization and evacuation of air. Prior to a load application, the specimen was impacted at 190 locations with a 2.03 gm missile propelled from a compressed air cannon. One of three missile velocities was employed in each test. Finally, the specimen was subjected to a spectrum of cyclic pressure and partial vacuum representing wind pressures experienced by a window during a severe four-hour windstorm. Black and white print and color slide photography and video were used to record specimen behavior. Test results indicated that specimens glazed with a 3/4 in. anchor bead performed much better than specimens glazed with a 3/8 in anchor bead. Specimens with the PVB/PET interlayer glazed with an anchor bead performed much better than similarly glazed specimens with the PVB interlayer.