2012d), “Molecular-level simulations of shock generation and propagation in soda-lime glass

A non-equilibrium molecular dynamics method is employed to study the mechanical response of soda-lime glass (a material commonly used in transparent armor applications) when subjected to the loading con-ditions associated with the generation and propagation of planar shock waves. Specific attention is given to the identification and characterization of various (inelastic-deformation and energy-dissipation) molecular-level phenomena and processes taking place at, or in the vicinity of, the shock front. The results obtained revealed that the shock loading causes a 2-4 % (shock strength-dependent) density increase. In addition, an increase in the average coordination number of the silicon atoms is observed along with the creation of smaller Si-O rings. These processes are associated with substantial energy absorption and dissipation and are believed to greatly influence the blast/ballistic impact mitigation potential of soda-lime glass. The present work was also aimed at the determination of the shock Hugoniot (i.e., a set of axial stress vs. density/ specific-volume vs. internal energy vs. particle velocity vs. temperature) material states obtained in soda-lime glass after the passage of a shock wave of a given strength (as quantified by the shock speed). The availability of a shock Hugoniot is critical for construction of a high deformation-rate, large-strain, high pressure material model which can be used within a continuum-level computational analysis to capture the response of a soda-lime glass based laminated transparent armor structure (e.g., a military vehicle wind-shield, door window, etc.) to blast/ballistic impact loading