specific gravity from consolidation test
specific gravity from consolidation test
(OP)
is it possible to get the specific gravity of the soil from the consolidation test? and if so what is the procedure?
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specific gravity from consolidation test
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RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
yes BigH i was thinking of how to get the initial void ratio. now correct me if im wrong but dont you need the eo to draw the curve? to get the Cc and Cr...
since i can draw the strain versus p curve then 0 strain is the "top" of the curve?
RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
If you have the slope of the strain curve (what I call the consolidation ratio v. the consolidation index) you can then do a settlement calculation using the ratio value (without any consideration of void ratio).
Hope this helps (or adds to the other's contributions).
f-d
¡papá gordo ain't no madre flaca!
RE: specific gravity from consolidation test
so previously i had been using the data with some assumptions to calc the Gs:
from the saturated sample... wet density - dry density = water
water/62.4= weight
((take the last reading after the rebound + 0.5") - weight)*dry density = density of solids
density of solid/62.4= Gs
after the consol is it safe to assume 100% saturation?
i usually get "high" Gs values of 2.8-3.2... this is why im asking... thanks
RE: specific gravity from consolidation test
f-d
¡papá gordo ain't no madre flaca!
RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
My first assumption, backed up with several flex wall perm tests, is the final saturation of my normal soils will be between 87% to 96%. In a few cases, 100% saturation has been assumed, usually when the specific gravity seemed too low.
RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
now BigH and fattdad say to use the Cc and Cr from the e vs logp curve then i can find the eo. ok simple...
now am i mistaken or dont you need the eo to plot the e vs logp curve in the first place?
RE: specific gravity from consolidation test
I see your dilemma - in that you have a computer program that requires the eo rather than letting you plug in CR and RR values. If you assume eo say, of 2.65, use it to plot the e-logp' curve. Obtain Cc. To see the senstivity of Cc on eo, assume 2.75 and plot - get Cc(2.75) and assume 2.7. Expect Cc will not be "much different" given the accuracy of plots, etc. Then you can get eo by eo = (Cc/CR)-1 . To make your computer
RE: specific gravity from consolidation test
example:
an actual consol test, from the strain vs logp i got a Cc'=4.49 and Cr'=0.735=CR
now my program asks for Gs actually then calcs the eo. so i plugged in different Gs and the program reports eo,Cc and Cr for the e vs logp
Gs eo Cr Cc
2.6 1.895 2 13
2.7 2.006 2 13
2.8 2.117 2 14
2.9 2.229 2 14
3.0 2.340 2 15
now i assume these number are rounded... so this is what you expected but how do you know which Gs is the right one? if you use the Cr=2 then you get a low Gs of 2.4ish which isnt right.
now if you use the eo with the strain Cc' and Cr' you can calc the exact Cc and Cr. curiously the Cc/Cr for each Gs are the same.
thanks for your time...
RE: specific gravity from consolidation test
RE: specific gravity from consolidation test
im assuming you use CR as my Cr' not Cr
RE: specific gravity from consolidation test