The following is an excerpt.
In a new study, SIMLab and NDEA-researchers have used an alternative numerical technique to model ballistic impact on laminated glass. Watch Post doctor Karoline Osnes´s presentation at the 13th International DYMAT Conference.
In late September, Karoline Osnes presented the novel approach at the 13th International Conference on Mechanical and Physical behaviour of Materials under Dynamic Loading (DYMAT) in Madrid, Spain. Watch the presentation in the YouTube video above.
IN COLLABORATION WITH PARTNER NDEA
Karoline Osnes’s fellow authors on the recently published study are Researcher Jens Kristian Holmen (SIMLab and Enodo AS), Professor Tore Børvik (SIMLAb, SFI CASA and NDEA) and Researcher Tormod Grue from the Research and Development Department at the Norwegian Defence Estates Agency NDEA) – a long time partner of SIMLab and SFI CASA.
Laminated glass is a type of safety glass frequently used in blast-resistant windows and bullet-proof glazing. However, there are relatively few studies concerning the perforation resistance of laminated glass in the open literature. Laminated glass consists of multiple layers of glass and polymer. When impacted by a projectile, the polymer will keep the layers together. Thus, it will prevent large fragments from being ejected by retaining the shattered glass on the interlayer.
The research team have impacted double-laminated glass plates by 7.62 mm armour-piercing (AP) bullets. Experimental tests and numerical simulations determined both the ballistic limit velocities and curves. They tested two different configurations, one single pane and two panes stacked with an air gap in between. The striking velocities were between 375 and 700 m/s.
INTRODUCING AN ALTERNATIVE APPROACH
In the study, the researchers introduce an alternative numerical technique to model the ballistic impact through higher-order elements and a 3D node splitting algorithm. The simulations employ simplified material and fracture models for the glass and PVB. However, the team demonstrate the substantial potential of this approach to model ballistic penetration and perforation on highly brittle materials.
Both the residual and ballistic limit velocities are very well predicted.
The study’s title is «Perforation of laminated glass: An experimental and numerical study». It is published in the International Journal of Impact Engineering Volume 156, October 2021, 103922.
CASA-PRESENTATION AT DYMAT
DYMAT organized the 13th International DYMAT Conference in Madrid, Spain, 20-24 September. DYMAT org aims to bring together engineers and scientists working on the dynamic behaviour of materials. This research field is relevant in multiple applications. Examples:
- Crashworthiness in transport
- Terminal ballistics related to defence, shielding of satellites, of turbine blades and discs
- Blast effects due to industrial explosions and terrorist attacks
- Material processing such as high-speed shaping of metals
Including Karoline Osnes, 4 CASA’ researchers presented novel research at this year’s conference:
Martin Kristoffersen: CASA´s Experts on Ballistic Impact Shared News of Concrete at DYMAT
Benjamin S. Elveli: About Blasting Steel Plates and Why Material Properties Matter
Vegard Aune: Into the Physics of Extreme Blast-structure Interaction