soil cement mixt design

[ciubotaru]

can anyone help me with information related to design soil cement dams or slope protection? in my country doesen`t exist aggrements....

 

[cvg]

suggest you find an experienced geotechnical engineer and a lab to help you.
here is some basic information

http://www.publications.usace.army.mil/Portals/76/Publications/EngineerManuals/EM_1110-2-1913.pdf

 

[Ron]

Here is a link to the Portland Cement Association (PCA) (US organization) for the out-of-print soil cement inspector's manual. Lots of good info here.

PCA Soil Cement Inspector's Manual

There used to be a difference between the term "Soil-Cement" and "Cement Treated Base (CTB)"; however, in recent times these two terms have become to be used synonymously. You might search for CTB info rather than soil cement info. The PCA has a guide for CTB but it costs $25 US.

 

[ciubotaru]

I am civil engineer, now i work at a company with hidrotehnical profile (flood risk management or how its called ) and i study this tipe of solution....i have acces at university laboratoy and now i want to discover the basic parameters to can simulate in a software...geostudio or geo5....i make the proctor test for optimal humidity on a ground clay with 2% 4% 6% 8% percent of cement, i make shear test (sry if i am wrong-i`m not english ) for determin φ(friction angle) and c (cohesion) in CU,and now i want to determin permeability and E , filnal test will be edometric test. It is corectly?what can i do extra?

 

[ciubotaru]

thanks for everiting!

 

[cvg]

well, not certain what your objectives are. cohesion and friction angle are not the main parameters you would be testing in a soil cement design for a dam. and clay may not be an optimal material choice for soil cement.
you should be testing and specifying:
a) compressive strength
b) cement content
c) fly ash content
d) moisture / density relationship
e) durability tests
f) erodibility tests

in addition to the mix design, you should be constructing a test fill to establish the rolling pattern and suitable equipment and methods for compaction.

 

[ciubotaru]

thx cvg....now i read more and i download AST test and i will try to make your recomandation test.i make test on a sand clay...not a 100% clay....i make test with 2% cement and 4% until now...and i will make for 6% and 8% and maybe 10%....but i want to say if sandy clay have 22 degrees friction angle and 30 cohesion...with cement it improved at 30 degrees and 50 cohesion...I think that stability will be better...and the optimal moisture is 20-21 % for water.I think is corectly...i want to ask you....in this mixt you add fly ash?fly ash if i am not wrong is for high-strengh concrete but i think it`s a good ideea.

 

[cvg]

typical soil cement mix for dam and levee construction has a 7-day compressive strength of at least 300 psi and with good granular material is generally much higher, easily 700 psi at 7 days. the material would resemble concrete. Every project I have been involved with substituted up to 25% fly ash for the portland cement. important engineering properties are compressive strength, durability and resistance to erosion. For clay soil, I would think your cement content would be a lot higher than 4%, closer to 9%.

here is the spec for the last project I worked on which was a levee. This material was sand and gravel with very few fines:

For bidding purposes only, the following mix design parameters shall be assumed:
• 7 percent base cement content (5 percent plus 2 percent additional for durability and erosion)
• 15% of the Portland cement replaced by flyash
• The required minimum 7 - day compressive strength is 750 PSI.

Maybe you are thinking of a cement modified soil (CMS) which uses much less cement and resulting material is much different. I have not heard of this being used in a dam or levee though, typically specified for roadways.

http://www.cement.org/docs/default-...tion-of-mod-to-high-plasticity-clay-soils.pdf

http://www.cement.org/think-harder-concrete-/paving/cement-modified-soils-(cms)

http://www.cement.org/think-harder-concrete-/paving/soil-cement