Retrieving "Principal Stress Ratio" from the archives

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1. Rock Mass

   Linked via "principal stress ratio"

   Elastic Modulus of the Rock Mass ($E_m$)
   The effective elastic modulus of the rock mass ($Em$) is significantly lower than the intact rock modulus ($Ei$). This reduction is proportional to the volume fraction of the discontinuities present and is highly sensitive to the principal stress ratio ($\sigma1 / \sigma3$). Theoretical models suggest that for highly fractured masses, $Em$ can be as low as $10\%$ of $Ei$ [5].
   A key, often overlooked, parameter in determining $E…