Soft impact response of laminated glass plates

A laminated glass typically consists of two layers of glass and one layer of polymer. It is utilised in many applications in which the glazing is exposed to external threats like impact or blast. In this paper, damage development of laminated glass plates by soft impact is investigated in both low and high velocity regimes. Low velocity impacts (up to 4 ms^-1) were conducted using a drop tower. Soft impact was achieved by attaching a silicon rubber cylinder to a flat steel impactor, with a diameter larger than that of the rubber, which itself is backed by a 16.9 kg weight. Different velocities were obtained by dropping the weight from various heights. For high velocity impacts (up to 220 ms^-1), a gas gun apparatus was used. The silicon rubber cylinder was fired, using a sabot, in a 25 mm diameter barrel. High speed photography was employed to monitor the deformation and damage development in the laminated glass samples. Laminated glasses with different types of polymer interlayer were tested. The results show a better impact resistance for laminated glass with a stiffer polymer interlayer at both low and high velocity regimes.