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modulus of subgrade reaction(s)

modulus of subgrade reaction(s)

modulus of subgrade reaction(s)

(OP)
I know there are many posts on the topic(s) but I wanted to ask a more pointed question instead of a broad, generalized one: is there a single source that provides a "good" definition/description of each type of modulus, its application, "typical" values for each type of soil based on what you're dealing with, etc etc? I suppose I would like to see sort of a compilation of values for comparitive purposes and 'academic discussion' (so to speak) for say slabs, pavements, footings, piles, etc. I would like to be more comfortable with all the caveats and uniqueness of each. Plus, many places I have searched simply discuss a k value and I feel that many of those places perhaps intermingled the kh and kv parameters. On top of that, it seems like I've seen the values intermingled for the different applications too. Does anyone know of a single reference that thoroughly discusses all the many different applications, correlations with different test methods & soil types/consistencies/strength, ranges of typical values for each, etc etc? I would appreciate even a list of sources that discusses parts and pieces of what I have described. I have several sources myself but thought it would also benefit others by having a single location where the topic can be researched from.

I'm also in search of the Holy Grail in case anyone can help on that too...

Thanks in advance

RE: modulus of subgrade reaction(s)

A mate of mine from South Africa loaned me a book that I had been unfamiliar with and I strongly suggest one and all have a good look at it - Ralph Peck wrote a piece at the beginning saying that once you have looked at this book you will not look at geotechnical investigations/engineering quite the same . . .  You may find a lot of what you might want in it.

Roy E. Hunt:  Geotechnical Engineering Investigation Manual.

RE: modulus of subgrade reaction(s)

I correlate soaked CBR to k value using chart shown by PSLem.

f-d

¡papá gordo ain't no madre flaca!

RE: modulus of subgrade reaction(s)

(OP)
thanks for the input. i have quite a few references already but i'll try the hunt manual. while i realize it's "dangerous" to post lots of correlations in one spot here because some bonehead will pull the first number they see and try to use it. but basically i'm just trying to get more reliable reference sources from the eng-tips regulars on to one place...not necessarily a cheat sheet of values. usually i deal with k on pavements and slabs but i'm getting more involved in other areas now so i'm just trying to get a better handle on the technicalities instead of simply pulling numbers out of correlations table without understanding where the heck the values originate from. thanks again.

RE: modulus of subgrade reaction(s)

msucog, I too am presently involved in a re-evaluation of the subgrade modulus, but have your same problems, no single source exhaustive material appears to be available.

For the nonce, I'm using the Bowles' textbook guidelines from chapters 9.6, 10.5 and 16.14

They differentiate between vertical and horizontal, also the author has got very simple but accepted suggestion to correlate kh to kv and to get a dynamic modulus from the static.

All in all, if critically read, it possesses a logic in its own and allows to build a fast output set of values which covers all that is needed now in seismic areas (static and dynamic Kh and Kv).

Does not discuss specific modulus for bulkheads and walls if I'm not wrong.

When I have some spare tiem I'd also like to study the Gazetas article on foundations vibrations, in Feng's handbook, that's sort of a main reference for dynamic modulus of subgrade.

Plus all the material on the web, useful but sometimes confusing.

BigH, I'm pretty much curious about the Hunt's book, it's already in my wishlist.

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