It consists of two buildings, the largest of which contains 419 luxury apartments

The Millennium Tower is still sinking into the ground and tilting left and right

  • Leaning Millennium Tower.

    From the source

  • Maintenance work to support the base of the tower.

    From the source

picture

San Francisco's luxury Millennium Tower has been slowly sinking into the ground for years, and as a result the 58-story skyscraper has tilted an average of three inches to the north and west last year, according to the engineer in charge of fixing it. The $350 million project opened in 2009 and consists of two buildings, the largest of which contains 419 luxury apartments, including a luxury penthouse worth $13 million, spanning an area of ​​5,500 square feet. It is the tallest residential building in the city, and the tower's uneven loads have caused cracks in the surrounding pavement and basement walls of the adjacent smaller 12-storey building. Tenants were first notified of the problem in 2016, and by the end of last year the tower had curved a total of 24 inches to the west and 7.9 inches to the north, then sunk about 18 inches into the ground.

Although engineers are now working on stabilizing the skyscraper, a hearing in the city last week revealed that the tilt will last for several more months.

Experts blamed nearby construction projects, and a process known as "dewatering", for weakening the soil under the tower.

The repairs, costing $100 million, were announced in October 2020 after years of lawsuits and hearings, and are expected to be completed later this year.

According to the installation's chief architect, Ronald Hamburger, the building continued to tilt 2.5 to 3 inches north and 0.75 to 3 inches west through 2021.

The rate of inclination has decreased in recent years as the building has stabilized, but there have been ups and downs, including an increased tilt from September to December 2021. That period coincided in part with a two-month hiatus in construction over concerns that efforts to stabilize the tower might exacerbate the problem.

It is expected that the tower will continue to incline until September this year.

"Once the stilts are installed using hydraulic jacks, some of the building's weight will be transferred to these new pilings," Hamburger explained.

"This will reduce the excessive pressure on the floor and restore some of the tilt that occurred," he added.

Other leaning towers

The Leaning Towers are well known worldwide when it comes to ancient architecture, with towers such as Pisa in Italy, and Nevyansk in Russia, becoming famous for their tilts, but they have become tourist attractions, while the Elizabeth Tower in London (the clock tower that contains the famous Big Ben ) has a slight but increasing curvature, yet the slant of a modern skyscraper inhabited by the unstable terrain of one of America's most expensive cities presents a costly and contentious dilemma.

Secrets of the underground world of leaning buildings

Civil engineer John Borland says, “Tilts are relatively rare, but I think when you deal with leaning towers you have to be more careful because this tendency is more evident than in low buildings.”

"The problem with a high-rise is that you can see its tilt, which people don't like, it may be safe, but the owners of the building are not going to be happy at all," he says.

The Millennium Tower is 645 feet tall and is the fourth tallest building in San Francisco.

Designed and developed by Handel Architects, the apartments in the tower will continue to be sold while engineers work to fix it.

In December, a one-bedroom, two-bathroom apartment sold for $1.16 million, and a one-bedroom, one-bathroom apartment sold for $765,000.

Hamburger says the building is and will remain safe for residents.

"Since we expect that the rate of tilt will continue to decrease over time and will eventually stop, we do not expect the building to tend to become dangerous," he said.

"Analyses have been conducted indicating that the building can withstand at least 70 inches of inclination to the west and 30 inches to the north before its ability to withstand earthquakes is affected."

• It is the tallest residential building in San Francisco, and the tower's uneven loads have caused cracks in the surrounding pavement and basement walls of the adjacent smaller 12-storey building.


• Once the stilts are installed using hydraulic jacks, some of the building's weight will be transferred to these new pilings.

Follow our latest local and sports news and the latest political and economic developments via Google news

Keywords: