August 6, 2004
Based on recent events involving terrorist attacks on high-rise structures, as part of a company-funded study to investigate the capabilities of the new HEXDAM 7.0 software, EAI has developed a three-dimensional model of the blast effects of a truck bomb explosion in front of the Hudson Center, a hypothetical office complex in New York City. In this representation the model includes an entire city block containing a twelve-story hotel, a twenty six-story office building, a thirty-story office building, a raised plaza terrace, and an underground parking garage. More than four thousand panes of glass are included in the model. One hundred pedestrians are positioned throughout the complex by means of the HEXDAM Man.
For the case of the Hudson Center, as shown in Figure 1, the entire simulation was performed utilizing the High Explosive Damage Assessment Model (HEXDAM 7.0) software. For increased damage resolution, the various components of the office complex were subdivided into a total of 4944 substructures, including more than four thousand panes of glass. A panel truck containing 1000 pounds of high explosive is parked under the porte cochere in front of the hotel.
The one hundred pedestrians are posed in various standing positions, and are distributed outside of the buildings in the Hudson Center. As previously noted, each pedestrian is composed of twenty-eight internal components, and thus a total of 2800 body components were included in the simulation.
For the case described, with 1000 pounds of TNT located in the panel truck under the porte cochere in front of the hotel, HEXDAM was used to simulate the results of the detonation of the explosive charge. Both color-coded graphics and tabular data describing the results were generated.
Three sets of figures covering the entire office complex were generated, as shown in Table 1. In each set four views of the passenger compartment are presented, as indicated in Table 2.
Table 1. Description of Graphic Sets for Entire Hudson Center
Set # Description Figures .
1 Undamaged Hudson Center 1, 2, 3, 4
2 Undamaged Hudson Center with three-dimensional overpressure contours 5, 6, 7, 8
3 Hudson Center with color-coded damage and injury and with three-dimensional 9, 10, 11, 12
Table 2. Description of Graphics Views for Entire Hudson Center
View # Description Figures .
1 Hudson Center (Northwest View) 1, 5, 9
2 Hudson Center (Northeast View) 2, 6, 10
3 Hudson Center (Southeast View) 3, 7, 11
4 Hudson Center (Southwest View) 4, 8, 12
For Set #1, in the four views shown in Figures 1 through 4, all structural components of the office complex are color-coded blue, while all pedestrians are color-coded fuchsia.
For Set #2, in the four views shown in Figures 5 through 8, all structural components of the office complex are color-coded blue. Likewise, all components of the bodies of the pedestrians are color-coded fuchsia. As indicated in these four figures, the three-dimensional overpressure contours are also color-coded, ranging from red for high pressure to yellow for low pressure.
For Set #3, in the four views shown in Figures 9 through 12, all structural components of the office complex are color-coded for damage, with green representing no damage, yellow representing slight damage, orange representing moderate damage, and red representing severe damage. Likewise, all components of the bodies of the pedestrians are color-coded in the same manner for no injury, slight injury, moderate injury, and severe injury. The three-dimensional overpressure contours are also color-coded, ranging from red for high pressure to yellow for low pressure. Close inspection of the figures reveals that the overpressure contours match the location of the broken windows in the 30-story office tower.
In addition to the graphical displays for the entire office complex, additional graphical displays were generated for that portion of the office complex near the location of the truck bomb, the undamaged view of which is shown in Figure 13. As before in this figure, all structures are color-coded blue and all pedestrians fuchsia. Individual three-dimensional overpressure contours produced by the bomb explosion are shown in Figures 14 through 26 corresponding to overpressure levels in descending order from 500 to 3 psi, as indicated in Table 3.
Table 3. Three-Dimensional Overpressure Contours in Vicinity of Truck Explosion
Overpressure (psi) Figures .
In these thirteen figures the structures are color-coded blue and the
pedestrians fuchsia. In Figure 27 structures
are color-coded according to damage, and pedestrians are color-coded according