I mean after doing the compaction practice in various water contents and determining the dry density corresponding to each water content, what would be the equation of the resultant compaction curve? Assuming that there should be only one optimum water content, I think the quadratic curve can be the best option to fit the bell shaped results. However, I could not find anything in the literature (the compaction curve is drawn without presenting the equation or a line simply connected data).
I was wondering if you could introduce me any reference about this matter.
It is a matter of great importance to me to determine the optimum moisture content consistently for all of my materials.
I attached my data and the quadratic curve passing through them. could you please let me know what is the optimum moisture content in these compaction data series and what is the compaction curve for them?
Check out the following links:
Article Physical and Compaction Properties of Granular Materials wit...
http://www.dot.state.oh.us/Divisions/ConstructionMgt/OnlineDocs/2009MOP/SS%20840,%20850,851,%20S-1015/S-1015/S.htm
http://www.multiquip.com/multiquip/pdfs/Soil_Compaction_Handbook_low_res_0212_DataId_59525_Version_1.pdf
https://openprairie.sdstate.edu/cgi/viewcontent.cgi?article=3519&context=etd
Note that the last links provide significant information regrading the optimum moisture content and dry density for granular materials.
The question seems to expect that a curve fitted through some laboratory result points could exactly follow a physical equitation. As the article of Ming-liang Chen e.a. states: "Thinking of it in reverse, the statistical constant can be used as an engineering indicator to evaluate whether artificial aggregate is in good condition". So again, in soil mechanics we are not able to fit nature in generally valid equitations, but we try to fit them as best as possible in constants that come clear at the outer side of a black box. Meaning we denote what we see, not comprehending the manifold of appearances earth shows us. Then, one should also take into consideration that sampling and testing bring their own contribution to errors. All together, soil mechanics will always need to make use of safety factors on laboratory figures and on approximating equitations. Such until soil mechanics can make quick scale steps like in digital processing.
I have checked your data, your Maximum Dry Density corresponding to your optimum moisture content is arround the point N°4 you can then stop your test at the point N°5 or 6 it is abnormal to getting two summits on one compaction process
Dear Baye Oumar Diop
Thank you for your reply.
I appreciate your time.
Kind regards,
Ebrahim
Hi, I have a question related to this, and maybe some of you can help: I work with compacted clays for their applications as landfill liners. Why do we calculate the OMC for knowing the optimum conditions for the best compaction and then we apply the moisture corresponding to the 105% max dry density? Thanks
Hi, You must find the OMC to use the soil (clay) in its optimal mechanical state which corresponds to its maximum dry density, therefore to the effective tightening of the granular particles
Thanks Baye Oumar Diop. However my question was another. The max dry density is the desired point because is where the compacted clay has the least air voids, and therefore the highest strength without saturating the material. But for the experiments, this point at the max dry density (which corresponds to the optimum moisture content) is not used: instead, the moisture corresponding to the 95% of the max dry density (in the wet side) is the condition used. I was wondering why? Maybe to be sure that we obtained the least air voids?
Ok dear Mercedes Regadío if you use the moisture corresponding to the 95 % of the MDD (in the wet side of the curve) its possible that the clay wil not be in its optimum condition and then could be in an alternative situation of swelling-shrinkage after its implement
Ok dear Mercedes Regadío if you use the moisture corresponding to the 95 % of the MDD (in the wet side of the curve)
its possible that the clay wil not be in its optimum condition and then could be in an alternative situation of
swelling-shrinkage after its implement.
I recognize clay is the most complex material in geotechnical material
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