Study on the influence of sandwich glass structure on its impact resistance

In view of the impact resistance of PVB laminated glass, PVB laminated glass of 0.76 mm and 1.52 mm thickness was selected in this paper to form five different types of “2 + 1” and “3 + 2” sandwich glass, and hydrogen gun flying plate variable speed impact combined with CT scanning and three-dimensional reconstruction technology was adopted. The failure mode and crack expansion of glass specimens after impact are studied. The influence of different factors (sandwich thickness, sandwich number, and sandwich position) on the impact resistance of explosion-proof glass is analyzed comprehensively. The results show that increasing the number and thickness of sandwiches can reduce the widening and expansion of microcracks, decrease crack connectivity, and effectively resist plastic damage to glass specimens. The appropriate position of the sandwich helps to improve the load-bearing capacity of the glass specimens. Therefore, the thickness of the sandwich, the number of sandwiches, and the position of the sandwich all have an impact on the impact load capacity and crack development of laminated glass. In addition, the impact resistance of laminated glass is positively correlated with the thickness of the PVB sandwich but shows different damage sensitivity to different impact velocities, with the best impact resistance under its medium velocity condition. This paper provides a significant theoretical foundation for establishing selection criteria for explosion-proof glass by examining the factors that influence its impact resistance, thereby enhancing its safety performance.