Modulus of horizontal subgrade reaction.
Modulus of horizontal subgrade reaction.
(OP)
Hello,
I have just found this community and it is full of useful content. I was just wondering if anyone could point me to a method for calculating the horizontal modulus of subgrade reaction for various soil types.
I need a method for calculating this for a given laterally loaded pile in a given soil type both at the top and bottom of the pile.
Thanks for any help you may be able to give an apologies if I'm going over old ground.
I have just found this community and it is full of useful content. I was just wondering if anyone could point me to a method for calculating the horizontal modulus of subgrade reaction for various soil types.
I need a method for calculating this for a given laterally loaded pile in a given soil type both at the top and bottom of the pile.
Thanks for any help you may be able to give an apologies if I'm going over old ground.





RE: Modulus of horizontal subgrade reaction.
RE: Modulus of horizontal subgrade reaction.
Thanks for the table suggestion I'll look into it.
RE: Modulus of horizontal subgrade reaction.
I have a chapter on my thesis than can help you. The only bad thing is that is in spanish. If you know spanish here is the thesis link http://grad.uprm.edu/tesis/fernandezvaldez.pdf chapter 2.5 page 33.
If not, here are come references that can interest you.
Vesic, A.S. (1961b). "Beams on Elastic Subgrade and the Winkler hypothesis." Proceedings of
the V International Conference on Soil Mechanics and Foundation Engineering, Paris,
France, 545-550.
Reese, L. C., y Van Impe, W. F. (2001). "Single Piles and Pile Groups Under Lateral Loading".
A. A. Balkema, Bookfield, VT.
Ling, L. F. (1988). 'Back Analysis of Lateral Load Tests on Piles.' Report No.460, Civil
Engineering Department, University of Auckland, New Zealand.
Carter, D.P. (1984). "A Nonlinear Soil Model for Predicting Lateral Pile Response." M.S.
Thesis, University of Auckland, New Zealand.
Another way to determine the modulus is with lateral load test to instrumented piles. If you can determine the p-y curves that represent the specific soil-pile interaction, the modulus will be the slope of the p-y curve at determine depth.
Hope this would help.
Best regards.
RE: Modulus of horizontal subgrade reaction.
I am using the p-y matrix method suggested in the attached paper and wish to make the estimation based on existing offshore bedrock data which may be limited to just folk classification of the rock at different depths.
Is there a way of estimating the required penetration with the pile diameter, thickness, bending moment@top, lateral load@top , folk classfication or am I trying to achieve the unachieveable? Essentially I am looking for look up table for different soil types. I will look up the Tomlinson's piling book when I return to university.
Thanks again for you help!!
RE: Modulus of horizontal subgrade reaction.
What you really have to make sure is that the pile is long enough to distribute the moments versus depth.
I would model it with L-Pile (if you have access to it) and that would give you a very good idea of the rotation, deflections and moments distribution with depth for you specific situation.
RE: Modulus of horizontal subgrade reaction.
it really looks like you want to achieve the unachievable as you say.
The paper you attached provides an algorithm, you need parameters though, such as elastic modulus, Su, shear modulus to get to the input parameter Kh.
One of my favorite sources for reaction moduli is Gazetas, 1990 (the article within FAng's handbook, foundation engineering handbook) with the perhaps misleading title of 'foundation vibrations', based on impedances which in static conditions become simple stiffnesses.
Parameters needed for lateral or swaying modulus K_HH are elastic modulus of soil (and its variation with depth) and pile.
RE: Modulus of horizontal subgrade reaction.
RE: Modulus of horizontal subgrade reaction.
Just wondering if you could send a copy of the paper "A Nonlinear Soil Model for Predicting Lateral Pile Response"? It is the only paper I cannot get via my university library.
Thanks for your help.
RE: Modulus of horizontal subgrade reaction.
For sand, you can use Kh=E'for preliminary analysis.