The Skyscraper Saved From Disaster By Secret Construction Teams

Due to the sheer variety of architectural projects a construction agency will work on, there are a lot of stories where engineers, architects and builders will find complications in a project and work together to solve them.

Often it is the latter who spot these issues, as contractors are regularly at the site inspecting and seeing the evolution of a blueprint into a completed structure, as well as being the ones to solve an issue as it appears.

One infamous example of this was the Citicorp Center skyscraper in New York City, where a miscalculation regarding potential wind loads meant that a 70-mile-per-hour wind could have taken the building down, risking thousands of lives in the process.

The original design for the skyscraper by William LeMessurier was notable and unusual due to its use of diagonal bracing and raised stilt design, but an architecture student by the name of Diane Hartley developed a thesis that suggested that the wind loads had not been calculated correctly.

This, combined with the proposed welded joints being replaced with bolts led to a combination of issues that would, if the building’s tuned mass damper did not work, lead to an estimate that a wind strong enough to knock the building down could come once every 16 years.

Mr LeMessurier was adamant that people were not made aware to minimise potential panic, and proposed welding plates over the bolted joints, which was contracted to a secret group of construction crews starting in August 1978.

Fortunately for the company, all three major New York newspapers had gone on strike, so the work could more easily be passed off as routine maintenance work and was finished before the newspapers returned.

There was a potential risk of Hurricane Ella testing the half-finished repairs but the wind eventually moved eastward instead, and people were only made aware of the issue several decades later thanks to an article by The New Yorker.