A disturbingly large number of America’s bridges are structurally deficient or functionally obsolete (see Better Roads’ November bridge inventory). But how many are “fracture-critical?”
Washington State’s collapsed I-5 bridge was fracture-critical when it was hit by a heavily loaded truck. But it is far from alone in the state of Washington in that classification and far from alone in Washington in being fracture-critical AND hit by a vehicle, according to a new report.
KUOW Puget Sound Public Radio reports: “There are more than 200 bridges in Washington that could collapse if a key part fails. They’re classified as being fracture-critical, just like the Interstate 5 span that plummeted into the Skagit River in May after it was hit by an oversized load. Out of those fracture-critical bridges, at least three others have been struck multiple times in the past five years. Experts say repeated bridge strikes can potentially cause catastrophic problems.”
Which begs the question: How many bridges in your state are fracture–critical? And how many get hit regularly?
Much of a worry will depend on the definition. After all, functionally obsolete or structurally deficient doesn’t mean the bridge won’t do its job. But our transportation infrastructure is aging and showing the frailties of age, and politicians who want to keep funding for its upkeep at its current woefully inadequate levels benefit from a public (yes, as in ‘voters’) that often doesn’t see the deterioration at work.
How would the pubic know if a bridge they cross is at risk? Rarely are shortcomings obvious. Fracture-critical bridges may be another of those problem we don’t come to grips with until there are enough I-5s to hold our attention for longer than a couple of days.