Wilshire Grand building will put Los Angeles back in the skyscraper business as city aims to rejuvenate its centre

The foundation site of the Wilshire Grand in LA - which is aiming for the largest concrete pour in history. Photograph: Zuma/Alamy

There's a very special hole in the ground in downtown Los Angeles. It's the site of the future Wilshire Grand, a 73-storey building filled with offices, retail and hotel rooms that will, when it opens in 2017, be the tallest building in the city, and the eighth tallest in the country. The project – a $1.1bn (£660m) investment – will be the first major skyscraper built in the city in more than 20 years.

It's a time span that's seen the global footprint of cities expand dramatically. Hyperspeed development in places like China and the Middle East have turned practically empty land into instant city skylines boasting the tallest buildings in the world. Long an American pastime, building skyscrapers has become a global game – and LA has largely been out of it.

So it is being welcomed with great pomp that LA is once again building tall. On Saturday, the developers of the Wilshire Grand will commence the pouring of the building's foundation, a banal yet in this case highly publicised procedure that will help ensure the 1,100ft tower can withstand the seismic and wind forces that will regularly test its structural integrity.

How the Wilshire Grand stacks up against some of the world's tallest buildings.

For reasons not purely promotional, the foundation's concrete will be dumped into the hole in one continuous pour – 21,200 cubic yards (16,200 cubic metres) of concrete dumped by 2,120 trucks over a 30-hour period, enough to earn the event a Guinness World Record. The continuous pour turned out to be the most economical way to fill the hole, according to Chris Martin, lead architect of the Wilshire Grand project, from LA-based firm AC Martin.

But pouring this much concrete at once is no small task. From sourcing the concrete and materials, to closing the streets, to keeping the concrete cool enough to set, the procedure is indicative of the technical evolution of building massive buildings. "You've never seen anything like this," says Martin. "I never have."

The entire site covers three acres, but the tower's foundation will take up about a football field's worth of space. It's a 17ft 6in hole ringed by 50,000lb (22,700kg) steel starter columns, providing a sturdy base for the structural columns that will rise to the building's highest floors.

After an opening ceremony led by the University of Southern California's marching band and attended by the mayor and other local politicians, a parade of concrete trucks will circle the site. At 16 stations, each truck will take about 10 minutes to dump its 6,000lb load of concrete into the hole before shuffling out and making way for another truck. Altogether they'll pour the equivalent of six and a half Olympic-size swimming pools full of concrete. It's a 30-hour relay that Martin calls "a ballet of concrete trucks".

More than 19 miles of plastic tubing will carry refrigerants through the mass for about two weeks, accelerating the cooling of the concrete's exothermic reactions enough for it to solidify. By then, the 17ft 6in thick foundation alone will weigh more than 90m lbs, the equivalent of four Eiffel Towers. Hyperbole and marching band theatrics aside, this project is more than just a fancy way to fill up a big hole. The foundation and its forthcoming tower are seen as an almost existentially important project for downtown Los Angeles, and the city as a whole.

"I think it has a potential to put LA on the map with respect to the world of tall buildings," says Daniel Safarik, of the Council on Tall Buildings and Urban Habitat, a group that tracks the development of skyscrapers. "Previously, LA was best known for blowing up tall buildings in movies, so you only had a few seconds to appreciate whatever architectural merits the US Bank Tower or the SunTrust Building had before it was destroyed by aliens or Bruce Willis." Historically, downtown LA was a capital for banks and oil companies. But in the early 1990s, banks began to merge together, consolidate offices or ditch the city for another state or country. "It created this huge vacuum in class A office space," says Martin.

The pressures and realities of the global market were manifest in empty office towers throughout downtown LA. It's been a slow rebound, and many in the city are hopeful that the Wilshire Grand is part of a new wave of investment downtown that will help the city compete internationally.

Not that LA has been sitting stagnant. Thanks to an adaptive reuse ordinance that has allowed the conversion of old and underused office buildings into housing since 1999, the downtown area has seen a return to prominence in this multicentric city. A population of more than 50,000 people is turning the central business district into a round-the-clock neighbourhood. But downtown LA requires more than the loft spaces and coffee shops of a gentrifying residential neighbourhood.

How the Wilshire Grand will fit into the Los Angeles cityscape - according to an artist's impression. Photograph: AC Martin

"Cities are globally competing with each other," Safarik says. "Regardless of their use, skyscrapers are seen as communicating the economic prominence of a city, and depending how big the country is, even the whole country. They're seen as a symbol of that place on the global stage. That's why it's gotten increasingly important for cities to build them."

The US was the birthplace of the skyscraper. Built in 1884, the 10-storeyHome Insurance Building in Chicago is widely recognised as the world's first, owing to the innovative use of structural steel to frame the building. Despite a rich history of American skyscrapers – from New York's art deco-topped Chrysler Building to the former tallest building in the country, Chicago's Willis Tower, to the now-tallest 1,776ft One World Trade Centre, which recently topped out in lower Manhattan – the US has been overshadowed in recent decades by other countries, especially in Asia.

Large economic and political differences mean that American cities are highly unlikely to go on a building binge of Chinese proportions, but they're also unlikely to stop building altogether. The Wilshire Grand is one example; downtown Manhattan offers many others. Even the long-sidelined, 150-storey Chicago Spire project has shown signs of waking from its slumber in the midwest.

For Los Angeles, the Wilshire Grand is proof that the city still has the cachet to go big. Yet it is also true that the developer investing the $1.1bn to build this tower is not from LA, nor even the US. The company behind the project is the South Korean shipping and airline giant, the Hanjin Group. But this is not a slur on LA; rather, it is proof the city is still able to compete in the increasingly competitive global market, according to Qingyun Ma, an architect and dean of the USC School of Architecture, who has worked on some of the tallest buildings now standing in many Asian cities.

"LA has always been a platform for global interest and for global ambition," Ma says. "My personal take is that this tower will cause a lot more ambition globally to come to LA, not only to downtown but to many places to build taller buildings." He is hopeful that a denser, more urbanistic city will result – but knows it will take time.

Martin, too, suggests the city will have to be patient. Its skyline won't grow like Shanghai's or Dubai's, but it will continue to grow. "I remember in '92 when we said we're not going to build any tall buildings for a long time," he says. "At the time I was thinking 20 years – and we're kind of on track for that."

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