8 Most Expensive Engineering Mistakes the World Has Seen

They say, whoever they are, that the greatest mistake a person can ever make is to be afraid of making one. Okay, but when it comes to construction stuff, it’s best to avoid them altogether. Not only they can be perilous, but quite pricey too! Like Tacoma Narrows Bridge in Washington.

The construction works were finished in 1940, a twin suspension bridge was unique and one-of-the-kind construction never seen before. In today’s equivalent, it costs about 1 billion bucks. Still, despite the amount of money spent, the bridge lasted slightly over 4 months. The engineers apparently missed one highly important issue — the wind. So, the bridge would sway and buckle — and that was probably because of a new construction method never used before.

By the way, the workers did notice something went wrong before the construction was finished, but they didn’t really pay attention to it and continued their work as if nothing had happened. They even nicknamed it “Galloping Gertie”. One day, the wiggly bridge rolled and rolled and collapsed, and millions of dollars spent ended up in the river. Good news — nobody got injured there!

The next one on the list is the Aon Center, one of the tallest buildings in Chicago today. Chicago is famous for hosting the first skyscraper ever, but the Aon Center has had bad luck. It was supposed to be an architectural masterpiece covered with exquisite Carrara marble from Tuscany. Bello! Yeah, it was incredible when it was just built, but it turned out the marble chunks weren’t thick enough, and soon after the Aon Center started sort of peeling, just like you peel a hard-boiled egg.

You can still find this building at the very same place where it was constructed, but it looks somewhat different from the original version. There has been a huge makeover in the 90s, and now there’s granite instead of marble. Not bad! Still, the repairs cost 80 million dollars. This does sound like a huge construction mistake.

Welp, the Aon Center may have looked like an egg for some time, but there’s another building with a construction mistake that made people feel like an egg on a frying pan. The Walkie-Talkie structure in London cost over 200 million pounds but guess what? There’s been a terrible engineering mistake. The glass facade had a peculiar shape as it was curved and that was the problem, as it acted like a giant concave mirror that reflected and focused the light.

Remember what a magnifying glass can do to the leaves if you catch the sunray? This comparison can be a bit of an exaggeration, but people inside the Walkie-Talkie claim it was no fun inside with a scorching temperature of above 160 F and charred carpets! They say the reflecting rays could even melt the cars parked nearby. The issue was solved thanks to an enormous sunscreen placed across the facade, which cost extra 10 million pounds.

Picture this: you want to relax a bit in Las Vegas, and you book a room in a luxurious 55-story hotel. There’s a Spa too! You know that the whole building is worth 8.5 billion dollars, and you’re sure nothing can go wrong. Ever... In fact, it can.

This is Vdara spa and hotel, and it has the same flaw the Walkie-Talkie in London has. For an hour and a half at midday, an intense concentration of scorching light from the main glass building reflects the sun rays onto a single point in the pool area. And this ray is so hot it can singe hair and melt plastic.

Yeah, I know there are places on Earth where hairdressers trim their clients’ hair with fire, but in this case, it’s not a beauty service, but a construction blunder. The curved glass surface acts as a parabolic reflector dish. Again, it’s the same magnifying glass trick, but imagine the sun’s rays going through a 55-story magnifying glass, woo-hoo!

Many stunning buildings have secrets or even construction mistakes behind them. The Sydney Opera House is no exception! It’s hard to believe that listening to the greatest operas of all time there, but the first people who spotted the mistake were the musicians. Thing is, they couldn’t actually hear their own music because of the acoustical imperfections. So, it cost 300 million Australian dollars to fix the issue.

Now imagine you’ve paid 300 million dollars for a building, but in the end, you got leaks, cracks, and drainage problems. The Massachusetts Institute of Technology doesn’t even have to imagine it, cause this situation did happen to them. An architect together with a construction company created Stata Center. Usually, the MIT buildings are referred to by their numbers, but Stata Center is an exception.

In 1998, Building 20 was demolished leaving behind only the time capsule to be opened in 2053. To replace it, Stata Center aka Building 32 was built. The design is quaint, and it sort of looks like a bunch of dancing robots. It got a lot of architectural criticism too — some people even describe it as an unfinished building about to collapse. The architect’s firm claimed the construction problems were inevitable, but they still had to pay 15 million dollars to make up for the problems.

Back in 1971, in Boston, The Hancock skyscraper was supposed to be built, but it was delayed by 5 years. The initial price was about 75 million dollars, but in the process of construction, it required more money, so the final initial price is 175 million dollars, which roughly equals 850 million today dollars.

The problems started during the excavation process — the temporary retaining walls didn’t turn out to be strong enough to hold back clay and mud, so they kind of warped. It’s like when you stack playing cards — you shift one in the foundation, and the whole stack falls apart.

The same happens when the soil shifts, which happened when building the Hancock. The pavements and the nearby buildings got cracked too, and the utility lines got damaged as well! Those damages cost at least 11 million dollars back in 1976, as one of the damaged nearby buildings won a lawsuit. Today’s equivalent of the first mistake is about 53 million dollars.

Another trouble is the blue reflective glass covering the skyscraper. You may think it acted as a magnifying glass again, but nope! Those glass panels would constantly detach and crash down on the sidewalk. The stronger the wind was, the higher the chances were that those panels would start falling down, so the police closed the nearby pedestrian streets once the wind reached 45 mph.

In the end, all the 10,344 panels were replaced — there was no other way out. Eventually, all of them would have crashed down due to the thermal stress caused by air expansion and contraction. It required an extra 5 to 7 million dollars back then to refurbish the building, which equals around 44 million in today’s dollars.

One more problem yet again — we all know the skyscrapers tend to sway a bit, right? Those sways usually come unnoticed, but not for the Hancock. People who lived on the upper floors started having motion sickness, so the right thing to do was to install a mass damper to minimize vibrations. Another 3 million dollars back then translated into 18.6 million dollars today. In total, 966 million today’s dollars were spent on the Hancock. Almost a one-billion-dollar disaster!

The last but not the least is the Leaning Tower of Pisa. That’s the kind of construction mistakes I like — despite its bizarre tilt, it is one of the best-loved Italian landmarks. The reason for the tilt is simple — the soil on the construction site was too soft to handle such a massive construction, and this is why the tower’s foundations are kind of destabilized.

The historians claim it was clear the tower would lean when the builders got to the third story, but they didn’t pay much attention to it and continued their work. Fun fact: the tower doesn’t lean, it actually falls --- very slowly.

So, it’s been falling since 1178, and each year it gets one to two millimeters closer to the ground. Still, in this list, this construction mistake is the only one that didn’t require any extra money but vice versa brought a lot of extra money thanks to the countless tourists who come to see it each day.