Concreters Like Round Piers

The initial pier & beam footing design from my Structural Engineer requires that sections of the strip footing are deepened down to "Extremely Weathered Rock", with minimum 200kPa bearing capacity. The design would work, but its not so easy to build.

My footings contractor would prefer round piers. The advantages are:

* There is up to 700mm of fresh fill to excavate through. Fresh fill readily collapses, especially with long trenches. So round holes are much better, as any attempt to collapse inwards, tends to be self-correcting, as the fill is trying to fall in on itself. The piers are drill first, inspected by the building surveyor, and then filled with concrete to just below the bottom edge of the beam (which is poured later)

* The deep pier holes is easily cleaned with the auguer (no need for a person to get down into a narrow deep tench to clean it out)

So, I have had the original pier & beam design re-done with round piers.