12/11/2022 0 Comments Millennium tower![]() ![]() In mid-July, the contractor started to install 61cm diameter piles along Fremont Street, which again resulted in an increase in the rate of tilt rate to the west.Īfter three more 61cm diameter piles were installed in August, all piling work was halted. ![]() In early July the contractor started to install 91cm diameter pile casings along Mission Street, which resulted in a small increase in the rate of tilting to the north. In May 2021 crews began to dig down to install 91cm diameter pile casings along Fremont Street, and by June 2021 the building had tilted approximately 6.3cm more to the west. Simpson Gumpertz & Heger senior principal director and engineer of record for the foundation retrofit Ron Hamburger has said that the tower’s settlement is primarily due to the “compression of the Old Bay Clay soils under the influence of the building’s weight, and prolonged dewatering of soils to accommodate adjacent construction projects”.īut the building continued to sink and lean throughout the repair process. ![]() This is supported by 942 precast, prestressed concrete piles extending approximately 24.3m below grade into the Colma Formation, a dense clayey and silty sand.īeneath the Colma Formation, the site is underlain by approximately 48.8m of marine and alluvial deposits, the upper layers of which are a stiff clay material known locally as Old Bay Clay. Located on Mission Street in the city’s downtown area, the building sits on a 3m thick, heavily reinforced concrete mat. The luxury tower has experienced excessive settlement since construction was completed in 2009. The troubled 58-storey residential building known as the Millennium Tower is now leaning around 71cm north west as measured from its roof, according to recent monitoring data seen by NBC’s Bay Area media outlet. A leaning high-rise in San Francisco that has evoked comparisons to the Leaning Tower of Pisa has continued to sink and tilt further, despite a US$100M (£82M) programme to fix it. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |