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The ESA's web report discusses subsidence and (more rarely?) elevation of the earth's surface. It works especially well in cities, “down to millimetres. The technique works well with buildings because they better reflect the radar beam” They're studying the phenomenon worldwide.
The Sentinel-1 satellites have shown that the Millennium Tower skyscraper in the centre of San Francisco is sinking by a few centimetres a year. [...] Completed in 2009, the 58-storey Millennium Tower has recently been showing signs of sinking and tilting. Although the cause has not been pinpointed, it is believed that the movements are connected to the supporting piles not firmly resting on bedrock.
The Register succinctly summarizes the whole situation in this report:
It was expected to sink less than 10 inches during its lifetime. It's already slumped 16 inches, is listing a few inches to the northwest, and it could sink a further 31 inches. The European Space Agency today said its Sentinel-1 satellites, having scanned the city's surface, have found that the building is disappearing into the ground at a rate of a few centimetres a year.
The problem appears to be that it was not built all the way down to the bedrock, and instead is sitting on a concrete slab with piles that go down just 60 to 80-feet into an underlying layer of landfill. Lawsuits against the developers are, as expected, in flight.
It's alleged that the city's building inspectors knew back in 2009 that the tower was sinking but did nothing about it – not even alerting the public nor the apartments' owners. San Francisco magazine's Lauren Smiley and Joe Eskenazi have detailed this ongoing clusterfsck at length here; it's worth the read.
The Register article also provides a copy of the ESA's displacement map for San Francisco with the tower's location marked and provides a link to a higher-res map.
(Score: 2) by bradley13 on Monday November 28 2016, @05:20PM
It's all well and good to blame the excavation next door - and it probably is aggravating the situation. However, having skimmed the linked articles, it seems that the building was sinking faster than expected before that excavation began. Moreover, it is sitting on bayside silt, and is built with a concrete frame instead of a steel frame - that saves costs, but makes the building massively heavier.
tl;dr: build a super-heavy building on silt, then look for someone to blame when it starts to sink.
Everyone is somebody else's weirdo.
(Score: 0) by Anonymous Coward on Monday November 28 2016, @06:24PM
it is believed that the movements are connected to the supporting piles not firmly resting on bedrock.
That would do it. Especially if the pile is not big enough. Sounds like someone found a way to speed up the project. By not digging another few hundred feet.
(Score: 2) by frojack on Tuesday November 29 2016, @12:59AM
Was the massively heavy frame an earthquake endurance feature forced on them?
Also, standard practice in buildings is to drive piles to the point of refusal, which is said to be just as good as bed rock, (and in fact in some places bedrock is not reachable).
Of course in the bay area you always have a liquefaction issue, and point of refusal may be won't remain constant over time.
No, you are mistaken. I've always had this sig.