Millennium tower lean11/6/2023 ![]() But before that, it must be stabilized, meaning that the piles first have to be placed on the sinking side of the tower and wait for the other sides of the tower to “catch up” or sink to the same level as the lowest side is today. There are some solutions being proposed by engineers (including the removal of the top 20 floors to reduce the tower’s weight), with the most dominant being to bore 275 to 300 “micro-piles” to anchor the building to bedrock. The opposite part however, blames an "inadequate foundation." Others blame the city of San Francisco for allowing Millennium Partners to anchor the building 80 feet into packed sand rather than 200 feet down to bedrock. They claim that during the transportation hub’s construction, builders pumped too much water from the ground, causing the water levels under the Millennium Tower to drop, resulting to the sand’s compression and the building’s sinking. The developers of Millennium Tower, Millennium Partners, blame the Transbay Joint Powers Authority, the agency responsible for the new transit center built right next to the tower. However, the 900 existing pillars of concrete piles only reach down to 91 feet below surface (28 metres). The soil under the Millennium Tower consists of layers of sand, mud, clay and landfill from the time of the gold rush, and you need to go 200 feet (61 meters) below the surface in order to reach solid rock. The first indications show that the problem lies in the fact that the building’s foundation doesn’t reach bedrock. However, last summer, the city of San Francisco and its engineers asserted the building is safe, even in the event of an earthquake. According to the experts, there's nothing to suggest the sinking and tilting are slowing down, much less stopping. ![]() The fact was also confirmed by satellites in late 2016, when Norwegian scientists, working with the European Space Agency (ESA), combined multiple radar scans from the Copernicus Sentinel-1 twin satellites of the same area to detect subtle surface changes – down to millimetres. Marinkovic, using signals from a satellite 500 miles above the earth, measures ground movements around fault lines in 2016, while studying the Bay Area, he observed that the zone around the Millennium Tower is sinking, in fact between 1.5 to 2 inches a year. One of them is Petar Marinkovic, who works with the European Space Agency to track earthquakes. The phenomenon is being surveilled by various engineers from all over the world. "There's enough of them, a spiderweb of cracks, that you have to be concerned about what's going on underneath," said Jerry Dodson, a resident who lives on the 42 floor, in an interview. After the suggestion of structural and geotechnical engineers, some of the building’s residents make daily rounds there to check on the stress gauges. Various cracks on the basement’s columns rising from the foundation indicate the reason. Now, the value of the units has dropped like a rock. The $550 million construction, as it was advertised, had attracted various buyers, from tech barons to San Francisco royalty and former football quarterback Joe Montana, that had paid millions to buy condos there. The problem is that the concrete tower is sinking -17 inches so far- and has also started tilting (14 inches to the northwest), while it is estimated that it will continue sinking an additional inch per year. ![]() The Millennium Tower, located at 301 Mission Street in San Francisco, is a 58-story luxury high-rise that opened in 2009, and at that time it was acclaimed to be the tallest residential building west of the Mississippi. Huge cracks spreading in the building's basement force its residents to sell their high-priced apartments at a loss
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