"Work calls for transferring a portion of the building’s weight to bedrock from its existing foundation system. The fix, likened to putting a bumper jack next t

"Work calls for transferring a portion of the building’s weight to bedrock from its existing foundation system. The fix, likened to putting a bumper jack next to a flat tire, relies on drilling and jacking 52 concrete piles—socketed more than 30 ft into the bedrock that starts 220 ft below grade—under the north and west sidewalks. Piles would support a new mat section, known as a collar, tied into the existing mat." - The fix they've halted. https://www.enr.com/ext/resources/Issues/National_Issues/2018/12-December/17-December/S1002.jpg https://www.enr.com/ext/resources/Issues/National_Issues/201... https://www.enr.com/articles/50287-foundation-fix-to-start-next-month-on-san-franciscos-troubled-millennium-tower https://www.enr.com/articles/50287-foundation-fix-to-start-n...