The building was leaning 17" at the top when this work started. Within a year it is now leaning 22". That is a dramatic increase in such a short time.
It would appear the objections to the original plan were sound. The alternative proposal is to drill through the original foundation to set the piers from inside the building. My understanding is this would be more evenly distributed and attached to the original foundation evenly. Then jacks would be used to "climb" the piers to level the building - very slowly over time.
The original fix is cheaper because it relies on gravity to further sink the high corner of the building once the lower side is fixed in place by the piers, then once that has happened piers can be sunk on that side. It also spreads the cost out over a longer period of time.
The other objection to the original fix is seismic: if only one corner is resting on bedrock during an earthquake the building could be severely damaged.
How do you drive piles once the building is completed? Do you go to the basement (probably a parking garage), open up space with the floor above it, and drive short segments that are welded together? I thing one of the earlier plans was to do this all outside the building on the perimeter, but if that's not enough, it sounds really complicated.
They should put a big hydraulic shaker in the bottom of the garage and just shake it until it hits solid ground. Then punch a new door in on whatever floor happens to be at grade.
Comments
The building was leaning 17" at the top when this work started. Within a year it is now leaning 22". That is a dramatic increase in such a short time.
It would appear the objections to the original plan were sound. The alternative proposal is to drill through the original foundation to set the piers from inside the building. My understanding is this would be more evenly distributed and attached to the original foundation evenly. Then jacks would be used to "climb" the piers to level the building - very slowly over time.
The original fix is cheaper because it relies on gravity to further sink the high corner of the building once the lower side is fixed in place by the piers, then once that has happened piers can be sunk on that side. It also spreads the cost out over a longer period of time.
The other objection to the original fix is seismic: if only one corner is resting on bedrock during an earthquake the building could be severely damaged.
How do you drive piles once the building is completed? Do you go to the basement (probably a parking garage), open up space with the floor above it, and drive short segments that are welded together? I thing one of the earlier plans was to do this all outside the building on the perimeter, but if that's not enough, it sounds really complicated.
They should put a big hydraulic shaker in the bottom of the garage and just shake it until it hits solid ground. Then punch a new door in on whatever floor happens to be at grade.
The bedrock is over 100ft down, so that would be fun
They'd have to reinforce all the walls first.