More Critical State 1

[ElGreco]

Again about Sands.As you may know, in a v-lnp' plot, the CSL of strength for Sands is initially curved. This means that at low confining pressures we need to model the critical state line of strength apart from the final linear part which is much better defined. For this purpose, people use the bi-linear model which is an approximation regarding this initial part as linear and almost paralle to the lnp' axis and SOME people use an expotential function to model that part...Does any1 know the procedure or any reference about the expotental modelling of this?

 

[BigH]

Excuse me - but why is this not in the Soil Testing forum? Sorry but can't help on this - I did find some interesting points in Malcolm Bolton's book A Guide to Soil Mechanics. He was referencing a paper by Cornforth (1973 - ASMT STP523; and also by Rowe (Geotechnique 1969).