There are more than 54,000 bridges in the US in need of repair, says this study

Published: 3 February 2018
Categories: Headlines

Source: CNN

The latest figure comes from a report by the American Road and Transportation Builders Association, a group that advocates for strong investment in transportation infrastructure. Using data from the Federal Highway Administration, the group releases an annual Deficient Bridge Report.

This year’s report, looking at data from 2017, found:

  • There are 612,677 bridges in the United States.
  • Of them, 54,259 are “structurally deficient,” which means they have at least one key structural element in poor condition.
  • That’s almost 9% of all US bridges, and the figure includes famous ones like the Arlington Memorial Bridge and the Brooklyn Bridge.
  • Americans cross these structurally deficient bridges 174 million times each day.

The report found that the largest number of defective bridges are in:

  • Iowa
  • Pennsylvania
  • Oklahoma
  • Missouri

States with the smallest number of structurally deficient bridges are: Hawaii Delaware Nevada

What it means to be structurally deficient

Bridges are regularly rated for safety on a scale of 0 to 9, with 9 meaning “excellent.” In order to be considered structurally deficient, one of its major components must measure 4 or below. Being structurally deficient does not necessarily mean that the bridge is unsafe, but it does mean it’s in need of repair. Repairing the deficiencies is critical. Deteriorating bridges can lead to road closures…

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Resilience Analysis Grid

Published: 17 January 2018
Categories: Research

Author: Erik Hollnagel  Technical note publication date: 2015

Erik Hollnagel introduced the Resilience Analysis Grid as a method for accessing the resilience of a system by determining how it may perform in both known and unknown conditions.Hollnagel presents four capabilities or potentials that must be present for a system to exhibit resilient performance: 1) the ability to respond based on knowing what to do; 2) the ability to monitor based on knowing what to look for; 3) the ability to anticipate based on knowing what to expect; and 4) the ability to learn based on knowing what has happened. Because the four abilities make resilience performance possible, the resilience of a system can be assessed by identifying the extent to which each of the four abilities are present and supported in the system.

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Integrating Risk and Resilience Approaches to Catastrophe Management in Engineering Systems

Published: 17 January 2018
Categories: Research

Park, Jeryang, Thomas P. Seager, Palakurth Suresh Chandra Rao, Matteo Convertino, and Igor Linkov.  Risk Analysis 33, no. 3 (2013): 356-367.

Integrating risk and resilience approaches to catastrophe management in engineering systems provides a basis for understanding resilience analysis as a complementary approach to risk analysis. Previously, resilience theory in complex systems was dominated by ecologists and non-engineers. Park et al. argue that these perspectives on resilience are inappropriate for complex engineering systems because technologies are created with human intention.

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Resilience Engineering in Practice – A Guidebook

Published: 16 January 2018
Categories: Research

Edited by Erik Hollnagel, Jean Paréis, David D. Woods, and John Wreathall

Resilience Engineering in Practice provides a practical interpretation of a resilient system performance based on the system’s ability to adjust its functioning. A central aim is to determine how resilient performance can be achieved by effectively engineering the four abilities of a resilient system: respond to the actual, monitor the critical, anticipate the potential, and learn from the factual. Considering the four abilities from an operational perspective offers an evidence-based approach that starts from a ‘whole-system’ level and leads to operational details on a concrete level.

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