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Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
202-366-4000


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Bridges & Structures

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Recommendations for Bridge and Tunnel Security

Descriptions of Graphics

Figure C-1

Box Descriptions:

Box 1 - Decisionmaker consensus
Box 2 - Security information
Box 3 - Decsionmaker consensus
Box 4 - Engineering Analysis
Box 5 - Decisionmaker consensus
Box 6 - Importance Attributes

  • Historic/symbolic
  • Replacement value
  • Evacuation route
  • Regional economy
  • Transportation network
  • Annual revenue
  • Attached utilities
  • Military route
  • Exposed population

Box 7 - Weighting factors for combining attributes
Box 8 - Occurrence Attributes

  • Access for attack
  • Security against attack
  • Visibility as a target
  • Publicity if attacked
  • Past threats/attacks

Box 9 - Weighting factors for combining attributes
Box 10 - Vulnerability Attributes

  • Expected damage
  • Expected closure
  • Expected casualties

Box 11 - Weighting factors for combining attributes
Box 12 - Importance Factor (IF)
Box 13 - Occurrence Factor (OF)
Box 14 - Vulnerability Factor (Vfi)
Box 15 - Facility Risk Score (RS)

Flow

Box 1 goes to Boxes 6 and 7
Box 2 goes to Box 8
Box 3 goes to Box 9
Box 4 goes to Box 10
Box 5 goes to Box 11

Boxes 6 and 7 goes to Box 12
Boxes 8 and 9 goes 13
Boxes 10 and 11 goes to Box 14

Boxes 12, 13, and 14 goes to Box 15

Return to Appendix C

Figure C-2

Attribute Approximate %
Historical significance 11%
Importance as an evacuation 15%
Importance to the regional economy 25%
Importance to the transportation network 13%
Replacement value 8%
Revenue value 11%
Criticality of attached utilities 5%
Military importance 5%
Level of exposed population 7%

Return to Appendix C

Figure C-3

Attribute Approximate %
Access for attack 12%
Level of security 3%
Visibility or attractiveness as a target 18%
Level of publicity if attached 41%
Number of past threats 26%

Return to Appendix C

Figure C-4

Attribute Approximate %
Expected damage (ED) 24%
Expected downtime (DT) 33%
Expected number of casualties (CR) 43%

Return to Appendix C

Figure C-5

Facility Importance Factor
(Approximate)
Bridge 1 0.91
Tunnel 1 0.80
Tunnel 2 0.75
Other Facility 1 0.71
Bridge 2 0.50
Bridge 3 0.42
Bridge 4 0.29
Other Facility 2 0.22

Return to Appendix C

Figure C-6

Bridge 1
  Vulnerable Component     Mode of Access  
Main Pier Base A Pedestrian
Water Borne
Land Borne
Main Pier B Pedestrian
Water Borne
Land Borne
Deck Level at Piers Pedestrian
Vehicle
Anchor Element A Pedestrian
Vehicle
Anchor Element B Pedestrian
Vehicle
Main Tension Member Pedestrian
Vehicle

Return to Appendix C

Figure C-7

Tunnel 1
  Vulnerable Component     Mode of Access  
Plaza Pedestrian
Vehicle
Tunnel Structure Pedestrian
Vehicle
Mid-River Pump Chamber Pedestrian
Vehicle
A Land Vent - Building Pedestrian
Vehicle
B River Vent - Building Pedestrian
Land and Borne
Water Borne
C Land Vent - Building Pedestrian
Vehicle
D Land Vent - Building Pedestrian
Vehicle
Administration Building Pedestrian
Vehicle
Approach Viaduct Pedestrian
Vehicle
Approach Plaza Pedestrian
Vehicle
A Land Vent - Tunnel Ceiling Pedestrian
Vehicle
B River Vent - Tunnel Ceiling Pedestrian
Vehicle
C Land Vent - Tunnel Ceiling Pedestrian
Vehicle
D Land Vent - Tunnel Ceiling Pedestrian
Vehicle

Return to Appendix C

Figure C-8

Tunnel 2
  Vulnerable Component     Mode of Access  
Portals Pedestrian
Vehicle
Tunnel Structure Pedestrian
Vehicle
Mid-River Pump Chamber Pedestrian
Vehicle
A Vent Land - Building Pedestrian
Vehicle
B Vent River - Building Pedestrian
Vehicle
Water
C Vent Land - Building Pedestrian
Vehicle
D Vent River - Building Pedestrian
Vehicle
Water
A Vent Land - Tunnel Ceiling Pedestrian
Vehicle
B Vent River - Tunnel Ceiling Pedestrian
Vehicle
C Vent Land -Tunnel Ceiling Pedestrian
Vehicle
D Vent River - Tunnel Ceiling Pedestrian
Vehicle

Return to Appendix C

Figure C-9

Bridge 2
  Vulnerable Component     Mode of Access  
Approach Piers Pedestrian
Vehicle
Main Piers Pedestrian
Water Borne
Main Span Pedestrian
Vehicle

Return to Appendix C

Figure C-10

Bridge 3
  Vulnerable Component     Mode of Access  
Approach Piers Pedestrian
Vehicle
Main Piers Pedestrian
Water
Main Span Pedestrian
Vehicle

Return to Appendix C

Figure C-11

Bridge 4
  Vulnerable Component     Mode of Access  
Approach Piers Pedestrian
Vehicle
Main-Span Abutment Pedestrian
Vehicle
Water
Compression Members Pedestrian
Vehicle
Tension Hangers Pedestrian
Vehicle

Return to Appendix C

  Contents  
Updated: 06/25/2013
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000