Corelation between CBR and Field Density Test (Troxler)

[RamiCivil]

I am looking for the correlation between CBR test (Field Test) and the Field density Test by using the nuclear gauge meter (Troxler)

 

[Dirtguy4587]

I believe that SlideRuleEra has something on this on his website. Search previous posts - you may find something on this.

Also, please don't double post.

 

[Ron]

Look at your CBR curve! That is your correlation.

Plot the density on your curve, that will tell you the CBR value.

 

[iandig]

As Ron says, you need to look at the actual material you are using. Different soils will have a different CBR at the same degree of compaction. Just consider the difference between a granular and a cohesive soil. Also it is not just the density/degree of compaction you need to consider, you must also refer to the moisture content of the material. I find it better to plot the moisture vs the CBR, not the degree of compaction.
In general, a cohesive fill will have a CBR of around 2.5% when the density = 95% of the MDD from a 2.5kg rammer on the wet side, but it could be greater than 5% when it is dryer than this. Therefore the CBR vs degree of compaction is not linear, you have to account for the moisture of the material especially when the soil is cohesive.