A heat wave made this bridge too swole to function
Climate change can pose some unexpected challenges to infrastructure.It was so hot last week, even steel bridges were sweating. The DuSable Bridge in Chicago overheated enough to stop working. While it wasn’t dangerous for drivers, the bridge couldn’t open for boats, and had to be closed for a half hour while firefighters hosed it down with cold water.
The 98-year-old double-decker bridge shuttles two levels of traffic back and forth over the Chicago River, and opens its decks to the heavens to let sailboats pass through. Baking under the sun for days on end, the joints of the steel bridge swelled, and were stuck in place. Luis Benitez, chief bridge engineer for the Chicago Department of Transportation, says the surface temperature of the bridge had climbed above 100°F that week. The steel finger joints—long, finger-like parts that accommodate expansion as cars travel over the bridge—interlock leaving a bit of space between each part, but the heat caused them to expand enough to rub together. You can think of it like a bridge with arthritis; the joints had become too inflamed to move properly.
“The temperature was getting too hot, and the bridge isn’t just expanding longitudinally, it was expanding sideways,” says Benitez. “Those two pieces of metal started rubbing together causing friction. Everything is so finely tuned, if you tried to force them apart, those joints can come loose or the expansion could get damaged.”
For the finger joints to touch, Benitez says the steel would have had to expand around an eighth of an inch. That doesn’t seem like much, but in the world of sweaty steel, it’s enough to temporarily shut down a bridge.
Although heat waves like the one that suffocated most of the eastern U.S. recently won’t cause a bridge to suddenly collapse, spells of hot, humid weather can cause a lot of problems for infrastructure. Materials like steel, cement, and asphalt—basically the building blocks of every city—are eager to absorb heat, and can reach surface temperatures of 140 degrees on a scorching day.
Much more: https://www.popsci.com/heat-wave-bridge-infrastructure
Chicago Firefighters Hose Down Steel Bridge During Heat Wave
Firefighters had to hose down the DuSable Bridge in Chicago after the steel surface spiked to more than 100 degrees Fahrenheit.
= new reply since forum marked as read
But there are bound to be instances which have much more serious consequences. 
so fossil fuel billionaires and kleptocracies like russia and saudi arabia can maintain their profitability.
Like everything else with Trump, his appointments are doing whatever is in their power to undermine the progress we've made regarding environmental protection. 
Just like any other equipment with expansion joints - when they're locked up, any additional thermal expansion may put high stress on many bridge components such as column bolts. Hope they inspect this old guy thoroughly soon!
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I remember several years ago reading an article about the condition of bridges near me - and as far as I know they still haven't been repaired. The horrific collapse of that bridge in Minnesota 10 years ago should have been a national wake up call, but still little has been done - and the severe weather we've been having is only making it worse.
10 Years After Bridge Collapse, America Is Still Crumbling
Ten years ago, the Interstate 35W bridge over the Mississippi River in downtown Minneapolis collapsed, sending cars, trucks and even a school bus that were crawling over it in bumper-to-bumper rush hour traffic plummeting into the river below and onto the rocky shore.
Thirteen people were killed, 145 more were injured, many of them seriously.
The bridge collapse sparked immediate calls in Minnesota and across the country invest big in repairing and replacing the nation's aging and crumbling infrastructure.
A decade later, experts say there have been some improvements, but there are still tens of thousands of bridges nationwide that need to be fixed or replaced.
https://www.npr.org/2017/08/01/540669701/10-years-after-bridge-collapse-america-is-still-crumbling
Thanks for the link. That brought back some painful memories. Just like with wars and Republican presidents, Americans seem to have very short memories and our outrage and concern way too short-lived.
However, I blame our political system as well for not keeping these issues out front in the media. Every time we have a disaster like the Minnesota bridge in 2007 or I-40 bridge collapse in Oklahoma in 2002, politicians make all sorts of promises but rarely follow-through. Our public deserves to be kept abreast of progress on both inspections and repairs. Unfortunately, many Americans only seem to want to be entertained these days......
I found this review of bridge failures around the world interesting: https://en.wikipedia.org/wiki/List_of_bridge_failures
That list demonstrates the high cost of human error and complacency, although Mother Nature has played her part as well.
On a positive note, this bridge inspection and repair in Louisville is one example where the system actually worked: https://en.wikipedia.org/wiki/Sherman_Minton_Bridge (see "Closure of 2011–2012" )
Not certain, but I strongly suspect that inspection was a result of the campaign for improved inspections resulting from the Minnesota collapse.
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I realize it's a "too soon we forget" situation which doesn't inspire confidence. Glad to hear that they've improved inspections in your area. We've had such severe winters that even the roads aren't in great shape. And I appreciate the link!
The most infamous collapse we had around here was awhile back, but it hit close to home. The mother and daughter heading to a baby shower were distant relatives - Dad's side. And the three men on the bowling team worked for my Dad. And this was climate related even back then. This area was also hit hard by Hurricane Irene in 2011.
30 years ago: Bridge collapse kills 10
Bridge over the Schoharie Creek gives way in storm, sending vehicles plunging
Wednesday marks the 30th anniversary of one of the deadly natural disasters in the region's history: the collapse of a Thruway bridge over the Schoharie Creek that killed 10 people.
The April 4, 1987 collapse of the bridge in Fort Hunter, Montgomery County, came in the midst of a spring thaw and torrential rains that undermined the bridge's pilings. An investigation later blamed faulty construction for the collapse of the bridge: It's pilings were built on the riverbed instead of driven into the bedrock beneath the surface.
Here's what the Times Union wrote on the 25th anniversary of the collapse:
Three men returning from a bowling tournament. A mother and daughter heading to a baby shower. Two Shriners who had gone to a black-tie dinner and were heading home to Toronto. A married couple driving to Texas. A truck driver heading from Green Bay, Wis., to Goshen in Orange County.
One fateful moment brought them all together 25 years ago at 10:50 a.m. on a Sunday morning, April 5, 1987. As they drove along the New York State Thruway near Fort Hunter, the bridge collapsed. All 10 died.
The bridge came down during a spring flood caused by snow melt and torrential rains.
https://www.timesunion.com/local/article/30-years-ago-Bridge-collapse-kills-10-11045976.php
FILE--This is a April 5, 1987, file photo showing the collapsed New York State Thruway bridge over the Schoharie Creek at Amsterdam, N.Y. The bridge collapse killed 10 people who were traveling on the Thruway on the rainy Sunday morning. (AP Photo/ Jim McKnight, file)