Bridge Abutment Piles and adjacent Surcharged Embankment
Bridge Abutment Piles and adjacent Surcharged Embankment
(OP)
I am curious to see where this thread will go. This is not a case history but I think the following question can be raised more and more as accelerated bridge construction techniques are being utilized. Here are the possible project circumstances:
A row of 18 driven bridge abutment pile foundations are installed prior to construction of a 2-stage MSE wall embankment. The piles are 100 feet long through a fine-grained soil profile. The tips are established in a moderate end-bearing layer. The MSE embankment (abutment) is then surcharged with 10 feet of material in order to minimize the bridge approach "Bump".
Question: In an effort to minimize the potential for differential settlement (or differential stresses) within the pile cap, When (and why) should the foundation contractor be allowed to construct and cast the abutment pile cap and thereby tying the pile group together? A) While the abutment is under surcharge conditions; B) While under surcharge but at or beyond 95% of primary consolidation; or C) After surcharge has been removed.
Thanks for your time.
A row of 18 driven bridge abutment pile foundations are installed prior to construction of a 2-stage MSE wall embankment. The piles are 100 feet long through a fine-grained soil profile. The tips are established in a moderate end-bearing layer. The MSE embankment (abutment) is then surcharged with 10 feet of material in order to minimize the bridge approach "Bump".
Question: In an effort to minimize the potential for differential settlement (or differential stresses) within the pile cap, When (and why) should the foundation contractor be allowed to construct and cast the abutment pile cap and thereby tying the pile group together? A) While the abutment is under surcharge conditions; B) While under surcharge but at or beyond 95% of primary consolidation; or C) After surcharge has been removed.
Thanks for your time.





RE: Bridge Abutment Piles and adjacent Surcharged Embankment
RE: Bridge Abutment Piles and adjacent Surcharged Embankment
However, since skin friction (downdrag) mobilizes with very small settlement, all the pile should experience the same magnitude of downdrag (full magnitude of the soil column). No pile cap timing is needed if the capacity at tip elevation is designed for the downdrag magnitude (i.e., the 30' of soil can settle forever, but the total downdrag will remain the same). Agree?
RE: Bridge Abutment Piles and adjacent Surcharged Embankment
RE: Bridge Abutment Piles and adjacent Surcharged Embankment
Other posts seem on topic too. . .
f-d
¡papá gordo ain't no madre flaca!
RE: Bridge Abutment Piles and adjacent Surcharged Embankment
RE: Bridge Abutment Piles and adjacent Surcharged Embankment
f-d
¡papá gordo ain't no madre flaca!