No doubt you have heard about the Leaning Tower of Pisa, but have you heard about the Millennium Tower in San Fran?
I have been to San Fransisco a couple of times; what a great place to visit. The city is filled with interesting places and surrounded by beautiful landscape. The buildings of San Fran offer a cornucopia of architecture and history. There is also a newer building drawing a lot of attention. No doubt you have heard about the Leaning Tower of Pisa, Italy, but have you heard about the Millennium Tower, San Francisco?
This $350 million residential building opened in 2009 with a height of 645 feet or 58 stories. The Millennium is the tallest concrete structure in San Francisco, and the fourth tallest building in San Francisco overall. When opened the building was also the tallest residential building west of the Mississippi River.
The residences are pricey; penthouse units have sold for upwards of $13 million.
But, in 2016 the building residents and the public was notified of a shocking problem: the building was leaning and sinking!
An examination showed the building had sunk 16 inches with a two-inch tilt at the base and an approximate six-inch tilt at the top of the tower. In fact, the building is leaning toward the northwest, and has caused cracks in the building's windows, basement and the pavement surrounding the tower. Not to mention the plummeting of the apartment values. As of 2018, the sinking had increased to 18 inches with a lean of 14 inches.
Now all buildings are expected to settle, but a building the size of the Millennium shouldn't settle more than 6 inches. If you haven't already checked out the video; watch the marble!
So, what happened?
The city approved design for the foundation of the tower consisted of a concrete slab built on 60–90-foot-deep concrete friction piles through the fill and young bay mud, and embedded into dense Colma sand. Yes, you read that right: SAND! Now, a number of other buildings in the Mission Street’s area have used similar systems, but the others have pushed piles directly into the bedrock 200 feet below.
A tentative settlement was reached at the end of 2019 between residents, owners, the city developers and construction companies to fix the problem by driving 52 new huge piles into the bedrock below to make a new foundation.
So, what is the lesson?
It doesn't take a rocket scientist or in this case a structural engineer to figure out a foundation built on bedrock is much better than a foundation built on sand!
What is the foundation of your life? What is your bedrock? Do you have one and if so, what have you been doing to take care of your foundation?
Author Simon Sinek calls our foundation, "Our WHY", and he writes in his book Start With Why, "Finding WHY is a process of discovery, not invention" (p.214). Have you found your WHY, your foundation?
Here's to finding your WHY, your foundation,
Troy Vande Lune
Big Rock Leader