Caisson Wall
Caisson Wall
(OP)
I am reviewing a caisson wall that is typical for shoring purpose (king caisson alternate with filler caisson).
Does anyone know the theory of how the filler caisson inter-lock with the king caisson? or how the caissons can act as a wall?
It would be great if anyone could provide me some references.
Thanks!
Does anyone know the theory of how the filler caisson inter-lock with the king caisson? or how the caissons can act as a wall?
It would be great if anyone could provide me some references.
Thanks!






RE: Caisson Wall
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RE: Caisson Wall
I wonder if there is any guideline to determine the overlaps between piles. Any calculations involved?
Also, is there any other consideration when designing this wall?
RE: Caisson Wall
I dont think there is any hard and fast rules on this, it just needs to have sufficient interlock. the intermediate piles work mostly by arching action.
RE: Caisson Wall
look at: www.secantpile.com
RE: Caisson Wall
My understanding is that there are primary bored piles constructed first and then the intermediate (secondary) piles are constructed.
The primary piles are spaced at less than the pile diameter so that secondary piles are bored through the concrete cover of the primary piles. So in the case of 4' cover the overlap could be say 3'.
Of course the pile wall will then need horizontal support as excavation commences. This support can be similar to a diaphragm wall and could be steel struts, soil anchors or "top down" construction using the permanent floor slabs as work progresses downwards.
Joints in diaphragm walls can be a problem even though these are proprietry joints lowered into the excavation before casting. For a secant pile wall I can imagine joints could be an even bigger problem as they just rely on the integrity of the concrete at the intersection of the piles.
RE: Caisson Wall
Is there any guidelines or code available for the secant pile wall design? Especially a guideline on how to determine the interlock width between piles. I have to show that the wall is workable.
RE: Caisson Wall
I design the structural piers assuming the unreinforced piers support no load. The soil will arch between the structural piers so there isn't a great deal of load on the unreinforced piers. you need to look at the specifications for vertical tolerances to make sure you will always have an overlap given the length of the piers. If the driller needs to use casing you get more overlap than you counted on because the piers end up being larger diameter than specified.