What happened to the Citibank building NYC?

During the Citicorp Center engineering crisis less than a year after the building’s completion, emergency repairs were made after the tower was discovered to be vulnerable to collapse due to wind….

How was the Citicorp building fixed?

But rather than putting the stilts in the corners, they had to be located at the midpoint of each side to avoid the church. Having stilts in the middle of each side made the building less stable, so LeMessurier designed a chevron bracing structure—rows of eight-story V’s that served as the building’s skeleton.

Who is Diane Hartley?

The flaw was discovered by Diane Hartley, an undergraduate student at Princeton University who was writing a thesis on the building, and was communicated to the firm responsible for the structural design. LeMessurier was subsequently lauded for acknowledging his error and orchestrating a successful repair effort.

What was the structural issue with the Citicorp tower that was discovered?

In 1978, the skyscraper’s chief structural engineer, William LeMessurier, discovered a potentially fatal flaw in the building’s design: the skyscraper’s bolted joints were too weak to withstand 70-mile-per-hour wind gusts. With hurricane season fast approaching, LeMessurier took no chances.

Which two cities led the rise of the skyscraper in the United States?

New York and Chicago remained the center of skyscraper development, but most major cities in the U.S. had built skyscrapers by 1929, frequently as a result of competition between rival cities for status and investment.

What is the 59 story crisis?

CITY PERILS about a structural defect uncovered in June, 1978 in Citibank’s $175 million Citicorp Center tower which could have caused it to collapse in the event of a strong hurricane. Tells about designer William J.

Who was the structural engineer for the Citicorp Center?

LeMessurier was the structural engineer behind the uniquely designed Citicorp Centre Tower, which at its completion in 1977 carried the title of seventh tallest building in the world.

When was the Citigroup Center in New York built?

From the very beginning, the Citicorp Center (today, the Citigroup Center) in New York City was an engineering challenge. When planning for the skyscraper began in the early 1970s, the northwest corner of the proposed building site was occupied by St. Peter’s Lutheran Church.

What was the steel bracing system in the Citicorp Building?

Steel bracing system in the Citicorp Center building. LeMessurier began looking for anything he could use to justify the building’s integrity. He tried to factor in the building’s tuned mass damper, one of the first ever installed in a skyscraper.

How tall was Citicorp Center when it was built?

When it was built in 1977, Citicorp Center (later renamed Citigroup Center, now called 601 Lexington) was, at 59 stories, the seventh-tallest building in the world. You can pick it out of the New York City skyline by its 45 degree-angled top.