Defense Testing

 a Case Study with NSL8

 

Homeland security continues to be a serious concern for infrastructure in the United States and around the world. A large defense contractor was charged with developing a panel that was no more than four inches thick and capable of mitigating a 30,000 psi bomb blast. The panels were to be used on the inside of the tunnels in New York City. Inside the tunnels, a would be terrorist could park his car as close as 12 inches from the inside wall of the tunnel and set off the bomb almost certainly killing the pedestrians in the other cars in the tunnel and causing the tunnel walls to collapse at great expense to human life and public infrastructure.

 

The bomb blast test was done at EMRTC in Socoro, New Mexico. Testing done at 30,000 psi were successful for all of the competitors in the test. At 50,000 psi, all but two competitors were eliminated. At 75,000 psi, only one panel survived.

 

Then, NSL8 was included in the test.

The test pressure was increased to 150,000 psi in the film shown. This was accomplished by placing 100 pounds of TNT flake just 12” inches above the surface of the four inch thick panel. Four and one half pounds of C4 explosives was used as the detonator. The combination of the two explosive media and their close approximation to the panel (12”) combined for an explosive energy of 159,000 psi.

 

The structure of the panel was ½” of NSL8 on the strike face, a sheet of S glass, a one inch section of NSL8 and another sheet of S glass. The results were  impressive: no penetration of the ½” strike face, an indention in the shape of the TNT box in the first S glass panel, and no damage to the second layer of NSL8 or the second S Glass panel.