Is there a way to estimate Coefficient Friction without testing?

[leecan]

Hello,

I am designing a Concrete Retaining Wall, I have the Internal Friction ∅.
Can i get the Coefficient Friction by this formula? µ = tan(∅)

Thanks and Regards

 

[FixedEarth]

We normally use 0.67*Tan(Phi) for sliding friction coefficient.

http://www.soilstructure.com/

 

[msquared48]

That would give a FS of 1.5.

Mike McCann, PE, SE (WA)