Modulus of Subgrade Reaction for Rock

[kgaspar]

Does anyone have a good reference for determining
the Modulus of Subgrade Reaction for different types
of rock.

The information is needed for a soldier pile application
drilled into rock for a retaining wall.

I need typical values for Ks (modulus of subgrade) for different types and qualities of rock. There is a book titled, "Design of Plates on Elastic Foundation" by
Korenev and Chernigovskaja, Moscow 1962, I have a copy of a table from this text but it is in Russian. I would like to find this text translated or another text with similar information. If anyone has any information or ideas where I could find what I'm looking for it would be appreciated.

 

[Sean2]

Do you REALLY need to calculate the deflections so accurately in this application that you need to use the modulus of subgrade reaction?

If the rock is intact and fresh, the deflections in the rock may be small compared to the end deflections of the soldier piles. If the rock is fractured and weathered, you will not obtain reliable published values, and may be better modelling the material as a soil (a particulate medium).

Apoligies if you have already asked yourself the above question.

 

[boo1]

Table 401.4.1; CABO One- and Two- Family Dwelling Code; 1995 lists various Soil Bearing Capacities

 

The best way to estimate the k-value of any material, short of a lateral load test is the pressuremeter. While not exactly fool proof, nothing in geotechnical engineering is, there are correlations in the Canadian Foundation Engineering Manual that can be used. Good luck.