Subgrade modulus reaction

This is a soils question. Some search terms might be "subgrade modulus", "subgrade reaction", and the like. Look around and see what turns up.

Good Morning,

These are unclassified documents, free to download by the public.

Once you're into the US Army Corp of Engineer's Headquarters website, look for PUBLICATIONS, followed by ENGINEERING MANUALS (ie, EM prefix). There are several very good EM's that you can find your information in, all very long.

Since you're asking about Subgrade Modulus Reaction, I'm assuming that you're involved with the design of a highway or runway pavement, be it either a flexible or rigid pavement.

For flexible highway pavements, look for: EM-1110-1-1804 "Geotechnical Investigations",

or

EM-1110-3-131 "Flexible Pavements for Roads, Streets, Walks and Open Storage Areas - Mobilization for Construction".

Another good source of information is the classic soils engineering textbook "Foundation Design & Analysis", authored by Joesph E. Bowles, PE PhD. Older editions of this book are free for download in e-book format almost anywhere on the Net. Just complete a Google Search and you'll come up with many hits.

Good luck!

===Signed,

CaptMoosie, PE PhD

Civil, Structural & Environmental Engineer

In plain English...okay Modulus of Subgrade Reaction has units of pounds per cubic inch or kN/mm³. It is a property of a soil which indicates the amount of settlement to be expected for a given bearing pressure. If a soil has a modulus of subgrade reaction of 50#/in³, it means that a footing bearing on soil with a pressure of 50 psi (7200 psf) will settle 1 inch. If the soil cannot take 50 psi, it means that the settlement will be in proportion to the above, i.e. a footing with a bearing pressure of 25 psi will settle 1/2 inch.

Bravo ba/ael Bravo! 1 GA from me!

I was trying to make the guy work a little, but your answer was sweet & concise..........and much better then mine!

Thanks, CaptMoosie. I hope your snow shoveling days are coming to an end for this year. I hope mine are too but not yet.