Let’s examine the bridge inspection industry as it currently stands, and has stood for decades.
Every day, one hundred and seven million cars and trucks cross bridges, highways, and railroad tracks that missed their federally mandated inspections. Inspections are required by law to happen every twelve or twenty four months, however, many inspections are not carried out. They are either carried out late, or not at all. When inspections aren’t carried out, structures are more prone to develop deficiencies that, in turn, become catastrophic problems.
In the US, one out of every four bridges nationwide is deemed inadequate. Let’s take a closer look at a specific type of bridge called fracture critical bridges. The FHWA defines them as a “steel member in tension, or with a tension element, whose failure would probably cause a portion of or the entire bridge to collapse.” There are over 18,000 of these fracture critical bridges of which 8,000 are classified as “structurally deficient.” Meaning, that they are liable to collapse. The reason why these stats are so frightening is because bridges collapse without notice. And, when they collapse, they kill.
Please don’t think that these low standards of inspection only occur with lesser known travel roads and bridges. Even bridges like the Golden Gate Bridge have had delayed inspections. Why aren’t inspections taking place in order to properly maintain and prevent against deficiencies in our the nation’s bridges? This is primarily due to the incredible price tag that is more often than not, passed on to local governments that cannot afford them.
These routine inspections are costly and risky, even for inspecting bridges that are new or that most likely don’t have any vulnerabilities. But, what about the bridges that are older, or that may perhaps have some issues? Costs of inspecting these older, more worn bridges can be ten times the cost of a regular inspection. Because of this, the bridges that need inspection and maintenance the most are the ones that are more likely to be neglected.
Let’s take a closer look at these costs…
Cost Breakdown
According to The Columbus Dispatch, inspections of fracture critical bridges can cost “well into the six digits.”
Inspections are manpowered, manual processes that necessitate meticulous visual examination. Inspections can take anywhere from one day to one week. Inspectors must be hoisted into every nook and cranny around the whole structure because even a crack that is one eighth of an inch is problematic.
How do these men inspect the bridge so thoroughly? By being hoisted, flown around, hung, and dangled off of the edge, of course! To correctly inspect a bridge, many inspectors will need access to boats, cranes, cherry pickers, and, our favorite, the Snooper Truck, pictured below. Looks fun, huh?
This vehicle alone costs three quarters of a million dollars, not even taking into consideration the costs of fuel, maintenance, and operational training.
Inspectors are forced into physically challenging situations, where risk to themselves, the machinery, and the public is high. The insurance that one must pay to cover the individual and the machine is a staggering total.
You must also consider the costs of manpower, inspection vehicles, insurance, and the cost of traffic delays.
Why is all of this so pertinent right now?
According to The Columbus Dispatch, most of the bridges spanning the US were built “quickly and inexpensively.” Most of them were only meant to be operable for fifty years. Since most of these bridges were constructed in the 1960’s and 1970’s, that means that their time is up. Our bridges are expiring, and, since they aren’t being demolished or rebuilt, then the least that governing agencies can do is to ramp up inspections. But, how can local and state governments afford to ramp up inspections when they can’t even afford to meet the bare minimum inspection requirements?
Drones.
We spoke with an inspector that was headquartered out of Texas. He was interested in our help for a suspension bridge that he was inspecting out in Dallas. He outlined a typical inspection procedure for us. It included seven men, the construction of a scaffolding that spread across the entirety of the bridge, and a week of time. He asked us what it would cost, and how long it would take to use our drone services instead. We gave him a quote and told him that it would probably take a few hours at most. He was silent for a moment, and then, when he could finally speak again, he informed us that our quote for the entire project was equivalent to the cost of insuring one man on the job. He had been doing his job the same for decades, and in one moment, his whole business was altered.
Not only will your costs be slashed, but drones can also offer better inspection data than is currently being gathered by traditional methods. Drones can provide infrared data, 3D modeling, topographic maps, and high resolution footage that can zoom in on cracks or abnormalities at the sub-millimeter level.
With drones, local and state governments can get all of their inspection needs met and more within a few hours. No need to close down bridges, bring out heavy machinery, dangle men over huge heights, and pay tens, or even hundreds of thousands of dollars to ensure the safety of millions of people every single day.
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http://www.nbcnews.com/id/20998261/ns/us_news-bridge_inspections/t/late-inspections-bridges-put-travelers-risk/
http://www.dot.state.mn.us/research/TS/2015/201540TS.pdf
http://www.dispatch.com/content/stories/national_world/2012/02/05/u-s–bridge-inspections-vital-but-pricey.html
http://saveourbridges.com/basics.html