The rotary rig is set up on a tight infill plot off Bramford Road, pulling up stiff boulder clay with pockets of running sand. In Ipswich that mix is common. We see it from the Chalk outcrops north of the town down to the alluvial silts along the Orwell. The rig runs a continuous flight auger through the upper drift, then we switch to coring once we hit the Crag or the underlying Chalk. Every metre we log the cuttings, the torque, and the return flush. That data feeds straight into the pile design. A single borehole isn't enough here. We cross-check the driller's log with in-situ tests and lab classification. For piled foundations in Ipswich we typically run CPT soundings alongside the boreholes to pick up loose lenses that auger cuttings miss. And where the cover is thin over Chalk we use test pits to inspect the rockhead directly before choosing a socket length.
The shaft resistance you count on in August can be half that value by February if you haven't tested the till at its wettest.
