This tragedy shows the importance of inspection and cost of maintenance of infrastructure. In the U.S. there are approximately 600,000 highway bridges. It's estimated that a quarter of them are at their end-of-life mark (that avg being estimated by some at 70). Not counting over 1,700 bridges still in use built before the 19th century, the breakdown is something like this:
This is just bridges. There are also about 84,000 dams and in a decade or two a huge number of both of these will approach their end of life, just as a legion of civil engineers go into retirement.
A ton of bridges around the country are near their end of life and are in disrepair; something like a third of all bridges. This is mostly because so many bridges were built in the mid 20th century. The good news is states are starting to pay attention to this and are allocating more funds to address it.
I'm not sure about anyone else, but I'm pretty sure our bridges should be something considered important enough to keep maintained. :(
> 36 percent of all U.S. bridges (over 222,000 spans) require major repair work or replacement. Placed end-to-end, these structures span over 6,100 miles – and would take over 110 hours to cross at an average speed of 55-miles-per-hour.
Hundred year old infrastructure is not the most sturdy, obviously this structure was past the end of its design life (leading to its failure).
Maintaining a structure doesn't prevent the concrete from spalling (as the chemical bonds that bind the concrete age and degrade), nor does it necessarily pick up on failing earthen tunnels in hard to inspect areas.
Many bridges across the country are going on 100 years old, and have a ~50 year design life. Structurally they are deficient, often undersized for the modes of traffic using them, and structural failure (which is very possible) would likely kill people. US infrastructure needs heavy investment, rather than the neglect it has seen for decades.
"There are more than 617,000 bridges across the United States. Currently, 42% of all bridges are at least 50 years old, and 46,154, or 7.5% of the nation’s bridges, are considered structurally deficient, meaning they are in “poor” condition. Unfortunately, 178 million trips are taken across these structurally deficient bridges every day. In recent years, though, as the average age of America’s bridges increases to 44 years, the number of structurally deficient bridges has continued to decline; however, the rate of improvements has slowed. A recent estimate for the nation’s backlog of bridge repair needs is $125 billion. We need to increase spending on bridge rehabilitation from $14.4 billion annually to $22.7 billion annually, or by 58%, if we are to improve the condition. At the current rate of investment, it will take until 2071 to make all of the repairs that are currently necessary, and the additional deterioration over the next 50 years will become overwhelming."
You are ok with a bridge collapse every 10 years? Do you understand how rare bridge collapses are today and that this would be a massive increase in the rate of failure?
I don’t think we really have most bridges built to last 100 years. What I see most is built to last 50 years and then usually it is stretched by patching/fixes or ignoring the issues as those will be passed on to whoever is in charge politically when a bridge finally fails.
Tell me about it. In 2007, there has been a bridge collapse[0] that was mostly caused by inadequate maintenance. Two others (more recently) were accidents[1][2]. And these weren't some little bridges in the middle of nowhere. They were heavily used interstates (sometimes crossing rivers). You can't miss them.
I live in a city that has three major rivers in it, and more bridges than any other[3]. Things like these give me the willies.
If you look at the Wikipedia List of Bridge Failures [1], since 2000, the US has had 28 bridge failures, over double the next highest entry on that list. Bridge failures are big enough events that, for developed countries, there's little chance of missing significant ones so we can treat the data as mostly reliable.
Per capita, there are some countries higher like Canada. but it's pretty clear that US bridges are unusually bad compared to most other developed countries.
That's interesting. I know that they used to be a lot more. Perhaps we should be glad that most of the bridges we drive over were built before FEM, and they just used a lot more steel. I wonder how well a bridge designed with a 25% safety margin is going to perform when it's poorly maintained for 50 years and rusting like a lot of bridges in the U.S.
This seems like an easy excuse for what happened here. If you can't maintain those 450 bridges, then don't keep 450 bridges. Remove 150 of them and maintain the other 300. You can't just ignore 450 bridges and hope nothing goes wrong because you can't afford to maintain 450 bridges.
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