Undrained analysis in OGS

[pavanbhukya]

Dear @maripicod,

I am Pavan, an OGS user. I think this recent thread might help you.

Reg. the sign convention of 'InitialEffectiveStressField'

Dear Prof. @Thomas_Nagel, I was solving the HM coupled problem of a footing on the homogeneous soil media using the MCC model. I have used the InitialEffectiveStressField option in .prj file to simulate the initial stress state. <parameter> <name>InitialEffectiveStressField</name> <!--effective stress!--> <type>Function</type> <expression> sxx </expression><!--xx--> <expression> syy </expression><!--yy--> <expression> szz </expression><!--zz--> <expression>…

When you use HydroMechanics, it considers the coupling effect through Biot’s poroelasticity theory. Hence, if you apply any load, excess pore pressures will definitely develop, given that you have reasonable permeability and a finite Biot coefficient. In the post I tagged above, I used a very high permeability to make the drained material wanted, as per my requirement.

Nevertheless, you will find the steps to activate effective stresses with hydrostatic gradient in the above-mentioned post.

I hope this helps.

Thanks
Pavan.