Wet clay

[rookery]

Morning All, We started to do a driveway last September but as soon as we got down150mm the clay was so wet the 1.5 ton digger started to sink in. We have waited till now to see if it dries out but hardly anything. The finished top course will be block paving. My question is this. Do you think that if I dig down about 200mm then put down terram followed by about 75 mm crushed then two layers or reinforcing sheet one just to the side of the other one to cause about 75 mm holes, followed by another 125mm crush this will stop any sinking Last September we put down 150mm crushed on terram and drove a pickup over it and it just squeezed out either side of the tyres. any help please, my first post so hope its in the right place. Thanks.

[Tony McC]

Last September? So not a rush job then?

It sounds as though the sub-grade is just too soft, so you'd be looking at something like.....

Commercial grade geo-textile
150-200mm capping layer of suitable material (DTp2 or Crusher Run 75mm)
Geo web stabilisation
150mm improvement layer of suitable material (DTp2 or Crusher Run 75mm)
Commercial grade Geo-Textile
150mm sub-base Type 1

If the ground is really bad, the capping could be 200-600mm (in layers n.e. 200mm), and the improvement layer could be swapped for a DBM or lean-mix concrete base course.