Is there a way using fish to apply hysteretic damping, based on the Darendeli equations, which is dependent on the overburden (or on the confining) stress?
If use of a single modulus reduction curve/damping curve is unrealistic, you can make the hysteretic damping depth-dependent (less damping and modulus reduction at high mean stress). You can create several groups depending on the depth and then use different hysteretic damping curves for each group. Or you can use fish code and loop the whole model and assign different hysteretic damping curves based on the mean stress.
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