How one design flaw almost toppled a skyscraper - Alex Gendler

TL;DR

A mistake in the Citicorp Center's construction was discovered, leading to a secret reinforcement to prevent collapse.

Transcript

In 1978, Diane Hartley was writing her undergraduate architecture thesis when she made a shocking discovery. Her paper focused on the Citicorp Center, a skyscraper in midtown Manhattan. And after weeks poring over the building’s plans, she’d stumbled on a potentially deadly mistake. An oversight that threatened to topple the 59-story tower into ... Read More

Key Insights

• 🎨 Citicorp Center's design flaw threatened collapse into a densely populated area.
• 💆 William LeMessurier's innovative solutions, like the mass damper, ensured building stability.
• 🌃 Secret night-time reinforcements were conducted to prevent a potential disaster.
• 📰 The public remained unaware of the crisis due to a newspaper strike during the reinforcement.
• 🛟 Diane Hartley's diligence in uncovering the mistake saved lives.
• 🛟 The Citicorp Center crisis serves as a cautionary tale for architectural oversight.
• 😮 Proper structural integrity reviews are crucial for high-rise buildings.

Questions & Answers

Q: What was the potentially deadly mistake discovered in the Citicorp Center's design?

The mistake involved cheaper and weaker bolted joints replacing the original welded joints in the building's exoskeleton, making it vulnerable to collapse in high winds.

Q: How did William LeMessurier address the building's vulnerability to strong winds?

LeMessurier installed a 400-ton tuned mass damper to counteract swaying and reinforcements were made to the bolted joints to safeguard against power outages during storms.

Q: Why was the reinforcement of the Citicorp Center kept secret?

The reinforcement was kept secret to avoid panic and sudden evacuation in a 10-block radius while also ensuring the safety of residents and preventing public alarm.

Q: When did the public become aware of the near-disaster at the Citicorp Center?

The public learned about the Citicorp Center crisis in 1995 through a New Yorker article, revealing the close call with disaster and Diane Hartley's crucial discovery.

Summary & Key Takeaways

• Diane Hartley discovered a deadly mistake in the Citicorp Center's design that could cause it to topple.

• Chief structural engineer William LeMessurier took precautions to reinforce the building's structure.

• Secret night-time reinforcements were carried out to prevent disaster during a potential hurricane.