Tallest Building In Western U.S. To Start With Big Pour
The 73-story, 1,100-foot tall Wilshire Grand project represents a $1.1 billion private investment by a Korean conglomerate in the city’s downtown, long an area of neglect but now experiencing a development revival.
“It will give downtown Los Angeles a new identity,” says José Huizar, a City Council member representing the area. “It’s going to help reshape the downtown skyline in a good way.”
After spending more than a year demolishing the old hotel on the site and digging a 100-foot hole for the building’s footings, architect and project manager Chris Martin says workers plan to pour the concrete foundation in one huge effort Feb. 15.
The project will attempt to set a Guinness World Record with the largest continuous concrete pour ever, Martin said. More than 2,100 truckloads will deliver 21,200 cubic yards of concrete weighing 82 million pounds.
The parade of concrete trucks will be led to the site by the University of Southern California marching band and a gaggle of local dignitaries who will mark the construction milestone with developers.
Pouring the massive amount of concrete at once allows workers to save several weeks’ time over a more normal, slower pour, Martin said, and will yield one solid, connected foundation rather than requiring mechanical connections between sections.
But pouring so much concrete at once has its downsides, mainly heat created by chemical reactions inherent to the process. To keep the concrete from overheating, which could cause the concrete to crack and ruin, workers have installed 19 miles of refrigeration piping amid the foundation’s steel reinforcement that will cool the process.
“We’ve gotten experts from all over the world to advise us on this,” says Martin, a third-generation architect whose grandfather designed City Hall in the 1920s.
“We’re baking a big cake.”
Because of its location in a seismically active area, the building will have what are in effect large shock absorbers, Martin said. At its top, the building will sway as much as 5 feet in high winds. “It’s so slow you just don’t notice it,” he said.
The project will be the tallest structure west of the Mississippi River, its developers say, when its 160-foot spire is included.
The building will house a 900-room hotel, with the lobby located on the 70th floor, with floors also for offices, retail and parking space.
Central to the design and the building’s height claim, was a relaxation in building requirements by the city, which for half a century has required downtown buildings to have a flat roof for landing a helicopter in case of a fire or other emergency. Without that requirement, Martin’s firm was able to design a glass pediment that will glow with colors at night and cover the top-floor “sky lobby.”
Huizar said that the required helicopter pads were almost never used and that new regulations recognize other safety features in construction materials and techniques.
“For decades we required these flat-top rooftops,” Huizar said. But with the change, he said, designers were free to plan “a more creative rooftop” while still meeting safety needs.
The developer of the project is Hanjin Group, which operates Korean Air Lines and Hanjin Shipping Co., both of which are major players at Los Angeles International Airport and the port of Long Beach. Its chairman, Yang-ho Cho, has been active in the city and is a member of the board of trustees of USC.
The hotel is scheduled to open in 2017. Huizar says that when completed, the project will help revitalize downtown neighborhoods, which have seen a spurt of residential growth. Today 50,000 people live in the city’s downtown core area, five times what it was a decade ago, Huizar said. An estimated half a million people work in the downtown area.
A number of other recent projects have fueled that growth, including the entertainment and sports development L.A. Live, next to the Staples Center, and condos. A $140 million art museum is also under construction downtown.
“In the past, after dark no one would stay downtown,” he said. “People would work here and leave right away. There was no nightlife. It was unsafe. It wasn’t well kept. But now, when we have so many more people living downtown, there is demand for public amenities.”