Geotech Depth Question - CRR equation

[AngelaK]

Can anyone point me to cyclic resistance ratio (CRR) equation in the references? I couldn't find it!! I am taking geotech depth.

 

[Aviatrix85]

You have probably found the answer by now, but I'll provide what I found for anyone else who may have the same question

I found CRR mentioned in the FHWA-NHI-11-032 LRFD Seismic Analysis & Design starting in Chapter 6.

Equation is located on document page 6-30 below figure 6-13

 

[Aviatrix85]

I just worked a problem where the CRR was provided. We needed to determine the Factor of Safety against liquefaction.

Tau(resisting) = CRR * Pv'

I didn't see this formula anywhere in the references yet.

FS = Tau(resisting)/Tau(Driving/Cyclical)