Piling for Building Foundations

[Lazy Sod]

I was down at Southampton Hospital Yesterday. They are building a new Intensive Care Unit just to the left of the main entrance. There was very tall machine auger boring vertical holes.

So what's the method? Fill the hole with concrete and rebar, or is the hole a pilot for a steel pipe to be knocked in and that then filled with concrete and steel?

 

[Steveyboy!]

Concrete and rebar if they're augering it out first

 

[MrA.G.]

It is most likely a Continuous Flight Auger (CFA) piling rig. Basically they core down the required depth and remove the arisings. The centre of the auger is hollow so as they withdraw concrete is pumped in under pressure. After the the core has been filled the rig moves which allow a pretied reinforcement cage to be pushed down into the wet concrete mix.