January 3, 2006


As a follow-on to a previous explosive damage assessment model study, as part of a company-funded study by Engineering Analysis Inc., a blast scenario has been defined involving a car bomb attack on a specific structure, with a glass front face, containing a number of personnel. By means of HEXDAM 7.0 combined with HEXFRAG 7.0 a series of test runs have been carried out to determine the injuries to the personnel inside the structure.


The basic scenario involved a car bomb explosion in front of a bus station containing a number of occupants. The car bomb consisted of a charge with a 200-pound TNT equivalency. The car was parked 50 feet from the front face of the bus station. The bomb was elevated 3 feet above ground level.


The structure representing the bus station measured 180 by 114 feet with a height of 30 feet. The 180-foot front face was divided into four sections, each consisting largely of glass, with 93% fenestration. The glass was characterized as a double-glazed unit consisting of two 6mm toughened glass plates. The remainder of the front face consisted of 6-inch thick reinforced masonry. The two 114-foot side walls and 180-foot rear wall of the structure were composed of 8-inch thick reinforced masonry. The roof was corrugated steel decking. The 25 columns were constructed of steel with a frame designation of W18 x 35. The arrangement of the columns consisted of five rows spaced 28.5 feet apart, with the first and last rows coinciding with the front face and rear wall. In each row the five columns were spaced 45 feet apart with the first and last columns coinciding with the side walls.


Within the bus station 150 personnel were uniformly distributed in ten rows, with 15 persons to each row. All personnel were oriented to face the front glass face, and were posed standing upright, with each arm extending out to the side. For simplicity each person was assumed to be 6 feet tall, with a weight of 180 pounds.


The appropriate parameters were input into HEXDAM/HEXFRAG consistent with the description previously given. As already noted, primary attention was paid to the computed injuries to personnel due to blast and fragmentation.