ExpCC
Exponential Hardening Cam-Clay Model
This hardening law is identical to the one documented in ABAQUS manual (4.4.3).
Hardening
The hardening function is defined as
\[
a=a_0\exp\left(\left(1+e_0\right)\dfrac{1-\alpha}{\lambda-\kappa\alpha}\right),
\]
where \(e_0\) is the initial void ratio, \(\lambda\) and \(\kappa\) are material constants.
If experimental data is available, \(a_0\) can be determined as
\[
a_0=\dfrac{1}{2}\exp\left(\dfrac{e_1-e_0-\kappa\ln{}p_0}{\lambda-\kappa}\right)
\]
where \(p_0\) is the initial value of the equivalent pressure stress and \(e_1\) is the intercept of the virgin consolidation line with the void ratio axis in a plot of void ratio versus equivalent pressure stress.