When looking at designing a road or pavement foundation the designer needs to comply with the local council standards, and a geotechnical investigation must be undertaken inline with California Bearing Ratio (CBR Test) . This needs to be under taken along the proposed root of the new road or pavement. The testing will need to be taken at a frequency to suit the anticipated ground sub-grade type.
On a small site a minimum of three sample tests should be undertaken and for a longer road the test intervals should not be more than 40m apart.
The ground test report should include both in-situ and laboratory test results combined with the interpretation of this data which was used in the design CBR value, in accordance with the local council regulations and standards.
All laboratory tests should be conducted in line with BS1377 part 4.