Six weeks into Citicorp's repair, a major storm, Hurricane Ella, was off Cape Hatteras and heading for New York. Reducing sway was of special importance, because the Citicorp tower was an unusually lightweight building;, the twenty-five thousand tons of steel in its skeleton contrasted with the Empire State Building's sixty-thousand-ton superstructure. Five years later the needed individual sites were bagged for the fantastic total sum of $40 million ($9 million for the church plot) and the construction of the Citicorp Center began in 1974. Le… How did the engineers do it? The original church building was sold and demolished to construct the Grand Central Terminal in 1903. With only half the repairs finished, New York City was hours away from emergency evacuation. The acronym stands for "Special Engineering Review of Events Nobody Envisioned.". The northwest corner of the site was originally occupied by St. Peter's Evangelical Lutheran Church, which was founded in 1862 (as the Deutsche Evangelische Lutherische Sanct Petri-Kirche). For the next three months, a construction crew welded two-inch-thick steel plates over each of the skyscraper's 200 bolted joints, permanently correcting the problem. From the very beginning, the Citicorp Center (today, the Citigroup Center) in New York City was an engineering challenge. From the very beginning, the Citicorp Center (today, the Citigroup Center) in New York City was an engineering challenge. The student’s professor said that the building’s columns were misplaced. He convinced Citicorp officers to hire a crew of welders to repair the fragile building. Web site © 2000-2001 WGBH Educational Foundation. 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. They set the 59-story tower on four massive columns, positioned at the center of each side, rather than at the corners. Educators' Guide | Shop. | In 1905, the church moved to the location of 54th Street and Lexington Avenue, where it remained until the building was purchased by First National City Bank (later known as Citibank) in 1970. With hurricane season fast approaching, LeMessurier took no chances. The church allowed Citicorp to build the skyscraper under one condition: a new church would have to be built on the same corner, with no connection to the Citicorp building and no columns passing through it. In June 1978, LeMessurier received a phone call from an engineering student writing a paper on the Citicorp building. Thus, the Citicorp’s building had columns in the center of its sides instead of the corner so the corners cantilevered over the church. This Web site was produced for PBS Online by WGBH. Building Big Home | Site Map | Labs | Databank | Glossary Luckily, Ella turned eastward and veered out to sea. This design allowed the northwest corner of the building to cantilever 72 feet over the new church. Yet the damper, the first of its kind in a large building, was never meant to be a safety device. (The only building left intact on the block was the 880 Third Avenue from 1965, at the south-eastern corner, due to its relatively young age.) LeMessurier explained that there was a church on the northwest corner of the site that they had to build around. The 30-page document outlining the structural mistakes in the Citicorp building was called "Project SERENE." Citicorp Center was the first skyscraper in the United States to contain a. Bridges | Domes | Skyscrapers | Dams | Tunnels 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. Local Wonders | Who Builds Big? The Citicorp crisis of 1978 was hidden from the public for almost 20 years.