Permissible lateral movement of tied back caisson wall
Permissible lateral movement of tied back caisson wall
(OP)
Is there a generally acceptable lateral movement of a caisson wall parallel to an existing reinforced concrete 10 storey condo building which is 3.5 m distance from the proposed new caisson wall to the nearest existing building footing founding elevation? The new building excavation is about 13 m deep. We want to specify the permissible maximum lateral movement of the new caisson wall. The movement would be measured at the uppermost level of tiebacks (this corresponds approximately with the bottom of the existing building spread footing which is 3.5 m away).
RE: Permissible lateral movement of tied back caisson wall
RE: Permissible lateral movement of tied back caisson wall
Such walls can also be designed for at-rest earth pressures (i.e., about 50 percent greater design loads. When you design the entire state of stress on at-rest earth pressures, then you'd limit all the typical Rankine earth pressure deflections. You'll still have some potential movement; however. Clearly, you could design an inadequate structure for the at-rest earth pressures - a structure that won't fail, just deflect under the at-rest earth pressures. It's a cat and mouse game. The structure will trump the applied load, so make sure you structure doesn't deflect under the at-rest soil pressure!
f-d
ípapß gordo ainÆt no madre flaca!
RE: Permissible lateral movement of tied back caisson wall
I suspect that I am posing a question that no one would want to answer...I am just wondering if there is any general number that is often used in such situations...for example 10 mm or 12 mm or 14 mm or ...?
RE: Permissible lateral movement of tied back caisson wall
There is NO one answer to the amount of permissible movement.
The amount of permissible movement of a wall that YOU are designing is dependent on what your wall is supporting. Therefore, as pointed out in the other posts, you BETTER CARE about both the existing building and the new building.
Mike Lambert
RE: Permissible lateral movement of tied back caisson wall
f-d
ípapß gordo ainÆt no madre flaca!
RE: Permissible lateral movement of tied back caisson wall
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Permissible lateral movement of tied back caisson wall