Exactly, any sane structure is built with some redundancy so you should be able to temporarily remove a column or piece of wall to install the jacking equipment

Exactly, any sane structure is built with some redundancy so you should be able to temporarily remove a column or piece of wall to install the jacking equipment and then do the job. For the tokyo station building, they simply lifted the building a bit and then placed it on seismic isolators. Can be seen on page 14 of this: https://www.ejrcf.or.jp/jrtr/jrtr61/pdf/6-15_web.pdf https://www.ejrcf.or.jp/jrtr/jrtr61/pdf/6-15_web.pdf Or for the Kansai International Airport the huge terminal building was built on jacks from the start the artificial island it was build on settles at an unequal rate: http://www.kansai-airports.co.jp/en/efforts/our-tech/kix/sink/hudou.html http://www.kansai-airports.co.jp/en/efforts/our-tech/kix/sin... They measure the different parts settling and then have a bunch of guys that will go to the affected section and jack the columns appropriately.