Coeficient of subgrade modulus variation 2

[zliazmei]

Hi All,

Please can somebody provide me a tabulated values of relationship between Relative density of Soil and Coeficient of subgrade Modulus Variation. Both Terzagi And Reese relationships will be verry helpfull.

Thanks

Zmei

 

[1967pradyot]

You can refer this book "Foundation Analysis and Design" by J.E.Bowles where a table is furnished with this relation.

 

[zliazmei]

TNXS,

But this book is still not in Our library .
Unfortunately I need it urgently:-((((

Zmei

 

[BigH]

Do a word search on modulus of subgrade reaction in this site. There has been a lot of discussions in this regard. Warning: Focht3 absolutely against Bowles tabulated values (from my recollection).

 

[Focht3]

Boy, are you ever right on this one, BigH!

What are you planning to do with the values of modulus of subgrade reaction once you have "them"? (There's more than one...)

 

[Centeno]

Hi: If I have the soil study of a site and they give me the allowable soil bearing pressure of the soil to be 3 kcf. What is the Subgrade modulus of reaction of the soil? Hope anyone can help me.

Carmen

 

[Centeno]

In practice do you use Bowles suggestions for the subgrade modulus of reaction, ks equal to: ks = 12*Factor of Safety*Allowable Bearing Capacity????????
ks=12*FS*qa

Centeno

 

[Focht3]

Nope. I use the elastic modulus appropriate for the likely soil strain magnitude (about 0.1% for spread footings, strip footings and mats) and calculate the settlement for the assumed loads on the soil. And I use a Gibson-type variation of elastic modulus with depth, i.e.

E[sub]y[/sub] = E[sub]0[/sub] + (k * z)

Values for E[sub]0[/sub] and k are chosen based on local experience, with guidance from the following paper: "Initial Response of Foundations on Stiff Clay", by C.E. Williams and J.A. Focht, III. (1982) ASCE Fall Meeting, New Orleans.



Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[jheidt2543]

Focht3,

Where might one get a copy of that paper, if one wanted one?

jheidt2543@aol.com

 

[Focht3]

ASCE had copies for sale - you might check with ASCE's Publications department - 800-548-ASCE is the main number. Inquire about Preprint 82-531. Also have the reference I gave on 7-24-03 in case they ask.

The preprints sold for $2.00 at the Convention. I have no idea what they would charge now -



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