A concrete record for tallest building in western USA

William M. Welch | USA TODAY

LOS ANGELES – Workers building what is to become the largest skyscraper in the western USA completed pouring the massive concrete foundation Sunday and established a world record in the process.

More than 2,100 truckloads of concrete were poured continuously over more than 18 hours for the Wilshire Grand Center project, setting a Guinness world record for largest continuous pour, a Guinness judge said Sunday.

"Everything went about as picture perfectly as they expected,'' said Michael Empric, Guinness' adjudicator on the scene.

"It was kind of like a ballet of trucks, moving in and out all night, to get this record done,'' he said.

The overnight pour began with a Saturday afternoon celebration at the downtown construction site, where the University of Southern California marching band led the parade of concrete trucks.

Sean Rossall, spokesman for the construction project, said 208 concrete trucks delivered 21,000 loads of concrete weighing 82 million pounds, hauling the material from several plants around the region where the concrete was manufactured.

The 21,200 cubic yards of concrete was completely poured shortly before noon Sunday, besting a previous record of 21,000 cubic yards set by The Venetian hotel in Las Vegas in 1999, Empric said.

Because concrete heats up as it cures, the architect and contractors designed and installed a system of chiller pipes inside the foundation that will cool the concrete as it solidifies. Pouring continuously rather than in sections allowed for establishing a single solid base to support the building's weight without linking separate sections of foundation, architect Chris Martin said.

The $1 billion private hotel and office project is being built by a Korean group that owns Korean Air Lines.

Once finished, the 73-story skyscraper will reach 1,100 feet, counting its spire, making it the tallest structure west of the Mississippi River. It will be about 100 feet taller than the current tallest building in Los Angeles and the West, the U.S. Bank Tower. The hotel is expected to open in 2017.

"In L.A. I think people are enthused about downtown. They're excited about this building. ... It means jobs, jobs, jobs," Mayor Eric Garcetti told KABC-TV at the ceremony.