Algodoo

This scene is a detailed recreation of the Citicorp Building, one of New York City’s most iconic skyscrapers, built in 1977. It’s best known for its unique stilt-style structure, where the building is supported by four massive columns placed at the center of each side, rather than the corners — an innovative but risky design choice that became famous for its engineering flaw and the secret retrofitting that followed.

In this Algodoo simulation, the structure is rebuilt to demonstrate:

The elevated base with columns offset from the corners

The angled roof that houses the building’s original mechanical systems

The wind load and balance mechanics, showcasing how the unusual column placement affects stability

You can test the building’s strength against simulated wind or vibration to see how the design holds up — just like the real-life engineers did when they discovered its structural vulnerability.