Correlation between SPT, CBR and DCP 2

[DOD]

I need to know if there is a correlatión between SPT(Standard Penetration test), CBR(California Bearing Ratio) and DCP(Dynamic Cone Penetrometer). If tyou know something about this subject please let me know.

Thanks,
Daniel Denis

 

[fkd]

Take a look a the following thread:

thread256-18139 will help,


Fred

 

[72shortbox]

I have had a hell of a time tring to find some correlations
it seams like each firm has their own DCP with their own correlation to SPT. My own expiernec trying to relate SPT to CBR is worthless their is too much variation.

I did find an Army Corp manual " Planning and Desing of Road Airfields and Hellaports" they have a DCP with correlations to CBR, but you need that specific DCP

my solution was to run inplace CBR tests ASTM4429

 

[nbryan]

I believe there is a draft standard in the works
which correlates DCP (8 kg) w/ CBR.

Contact ASTM Subcommittee D 04.39 for more information.

 

[Wopshistos]

a lab cbr test is not that expensive that you should be thinking of avoiding one. Various formulae have been eveloped suggesting some form of comparison but the figures from those sources dont match in most cases ... so i gave up. The DCP is a good tool but again its difficult to relate the result to standard tests accurately. We tend to use it for relative stuff because its so quick and not as a tool to provide comprehensive SI.
Not much help was I?

 

[Riz]

Typical correlation between DCP and SPT values:
DCP value in mm/blow SPT value blow/300mm
5 50
6 44
7 38
8 33
9 28
10 24
12 22
14 18
16 16
18 15
20 14