Low Velocity Impact Resistance of Laminated Architectural Glass

Recently developed finite element algorithms are used to study the effect of glass ply geometry on low velocity, small missile impact resistance of laminated architectural glass. The impacts studied are those typically found during severe windstorms, in which debris such as roof gravel can attain sufficient velocity to break windows in large high rise buildings. Outside ply fracture and interlayer debonding are both incorporated in the finite element analysis. It is shown that glass ply geometry can significantly affect the impact resistance of laminated glass. Three-layer laminates are shown to offer better impact resistance than five-layer and seven-layer laminates of the same overall thickness. For three-layer laminates of the same overall thickness, those with thin outside glass plies provide better impact resistance than those with thick ones.