When constructing a pile with temporary casing, the pile diameter through the cohesionless (cased) soils is much greater, resulting in an increased shaft area and thus capacity.

Currently Pile can only specify one (the minimum) pile diameter.

It would be very useful to enable a check that the characteristic pile shaft resistance is greater than the characteristic pile action.

i.e. a factor of >1 on the shaft capacity alone

Pile currently treats soils in two broad catergories: drained and undrained, the drained soils have only an angle of friction and the undrained only the undrained cohesion. It would be nice if c-phi soils (e.g sandy clays, clayey sands) can also be considered.

It is currently not possible to apply both tensile and compressive loads in the same file to compare against the calculated resistances. The programme subtracts the tensile loads which are applied as negative loads from the compressive loads which are positive instead of recognising them as separate loads.

Where embedded pile retaining walls carry axial loads, it is common practice to analyse the section as a rectangular panel rather than individual circular piles (with a reduced end bearing co-efficient akin to a deep strip footing).

To date, we have achieved this by modelling an under-ream pile with different shaft and base diameters. However, it would be simpler and clearer if Pile could analyse a rectangular section. This would also be beneficial for calculation of axial resistance for diaphragm wall panels.

Refer to method of Hov et al from 2010 DFI Conference (attached).