BigH a question on a previous post!

[oneintheeye]

BigH,

you have previously talked about a relationship between CBR and bearing values and have placed a chart on sliderules site. (nice site slide, cheers). would you mind telling us where this chart is from? I have a tendancy not to trust internet until I can verify it myself!

thanks.

 

[BigH]

There are two charts posted. These were not taken off the internet but were from actual books I have.

1. CBR to AASHTO Class to Mod of Subgrade Reaction to CPT-SPT to CPT to SBPMT can be seen in Fang's Foundation Engineering Handbook, Fig 3.37.

2. CBR to AASHTO to R value to etc. - can be found in Baker's Highway Engineering Handbook (reference is in storage in Toronto so cannot tell you the Fig #.) - have also seen it elsewhere but can't remember off the top from where).

The one point that is not made, sadly, is as whether the CBR is a soaked value or an unsoaked value. This is one of the problems one notices all the time - nobody ever seems to give sufficient or concise details espeically wehre some ambiguity can exist.

 

[oneintheeye]

thanks BigH,

i wasn't implying you had sourced them off internet but if i was to make any reference to them I wanted a source for backup as I doubt our auditors would accept me saying someone off a message board passed them on!

Thanks again.

 

[belzer]

MRM does a nice job in explaining as an engineer. But, summer05, you seem to want the basics. The relationship between dry density and wet density is:

dry density = wet density divide by (1 + moisture content as a fraction).

e.g., Moisture content is 10%. Wet density is 110 pcf, then the dry density is 110/1.1 = 100 pcf.

I have gauge #'s of Troxler 3440
DD=129.0
WD=123.6
Moisture at 10%
95% compaction

using your formula above it doesn't work--

123.6/1.1=112.36 for DD.

What I need is how to get a WD and weight of Moisture having DD and %moisture

Thanks