Lateral deflection of raked/batter piles

[Grad1]

Dear Sirs,

I am curious to know if there is a reliable way of modelling (by hand-preferably) the bending moment response of a batter pile due to induced deflections resulting from consoliation settlements in a layer of soft material(6-7m deep) below an embankment (6-7m high) which has been preconsolidated by compaction and other ground improvement methods (and therefore will not settle as much as the soft material). The embankment supports a high level seating beam for a bridge (as obviously do the piles). The piles are bearing on rock. Any insight into ths would be greatly appreciated!

 

[Ron]

There are several ways to approach. I would start this way...

Assuming you have fixity in the pile below the soft layer (you'll have to decide just how far you go below the soft layer before true fixity occurs), then the pile becomes a cantiliver beam with two different, variable loads...the load of the compacted embankment and the load of the soft material (+ any material below the soft material but above the point of fixity).

 

[Grad1]

Thanks Ron, already did that - only note that in my case, the pile was fixed at the top (at seating beam) and pinned at the bottom (at rock bearing) and thus a propped cantilever with similar surcharges as you suggested. You mentioned other ways of approaching the problem, I would be very interested to discuss them if possible. I have found it difficult to find literature on the subject.