Initiating Stress

Usability
1

I’m having a problem trying to initiate the stress in the model domain. I need to set the initial stresses to lithostatic conditions, however, the four parameters that are necessary don’t allow a definition through a function. I have no problem initiating the temperature and hydrostatic pressure but because sigma requires a vector im struggling to fins a solution.
I may be missing an easy solution to this so would appreciate any help.

2

Hi Richard,

If I understand your question, you need some command like this one.

        <parameter>
            <name>InitialEffectiveStressField</name> <!--effective stress!-->
            <type>Function</type>
            <expression> 0.4 / (1-0.4) * ((0.2-1.0)*1000 + (1-0.2)*3000) * 9.81*y</expression><!--xx-->
            <expression>                          ((0.2-1.0)*1000 + (1-0.2)*3000) * 9.81*y</expression><!--yy-->
            <expression> 0.4 / (1-0.4) * ((0.2-1.0)*1000 + (1-0.2)*3000) * 9.81*y</expression><!--zz-->
            <expression>0.0</expression><!--xy-->
        </parameter>
    </parameters>

This link has some examples that may help you:
https://www.opengeosys.org/docs/benchmarks/hydro-mechanics/hm_groundequilibrium/

Regards,
María

3

Hi Maria,
Thank you for your help! I couldn’t seem to find that benchmark in my search!
All the best,
Richard.