A requirement of the foundation design for the house is to establish the soil type and bearing capacity of it to allow the structural engineer to design a suitable slab and sub base for it. A small rig was brought to site to undertake a ground bearing test by driving a hole into the ground down to 4 meters, and to also bring samples of the soil up to the surface for visual inspection and collection for lab testing.
Operating the mini piling rig
I was fully expecting to find rock chalk at about 1.5 meters as this is what we have at the top of the garden. I came as quite a surprise to find silty chalk with blue clay beneath it. Our plot is at the bottom of the valley where sediment must have formed.
Core sample from below ground
The soil was taken away for analysis to test its plasticity as this could have major consequences for the type of foundation design.
Divining for underground cables
It came as quite a shock to see bent coat hangers being used to check for underground cables and pipes. I am not sure I would rely on it 100% but he did find my underground mains power cable and also water connection to the house.