thanks for all the valuable feedback. I am going to try the undercut and replace with some surcharging solution, after the original geotech engineer takes another look at it and weighs in on this, since he will be responsible for the foundation design as well...
I would guess that a possible solution is to surcharge using the same material that we would use for the subgrade... Then all the excess spoil from the excavation can be moved off site or elsewhere on site?
To Oldestguy.. What is the most economical way to surcharge the site, and over what period of time does it need to be monitored? and also typically what depth to undercut the footings?
To others:
I have posted the soils report from 2000 ( eleven years old) online at
Your file's link is...
A two story duplex townhome was demolished 20 years ago on a project built in early eighties, because of foundation settlement, as much as 5 inches differential. Ten years ago I had substantial geotech investigation done, and as it turns out, there is poorly compacted fill under the building...
