Young's Modulus

Young's Modulus 1

Small Strain Young's Modulus 1 ($//<![CDATA[ \begin{array}{l}E_0\end{array} //]]>$) in Youngs_Modulus_1 is defined as:

$$//<![CDATA[ \begin{array}{l}\displaystyle E_0=2 \cdot(1+v) \cdot G_0\end{array} //]]>$$

Elastic theory, CPT in Geotechnical Practice p 74 and 94, NCHRP Synthesis 368 p 32

Where:
     $//<![CDATA[ \begin{array}{l}v\end{array} //]]>$ = 0.2 is applied and can be varied in the Formula Tool. Published literature states: $//<![CDATA[ \begin{array}{l}v'=0.2\end{array} //]]>$ applies for drained soils and $//<![CDATA[ \begin{array}{l}v_u=0.5\end{array} //]]>$ applies for undrained soils .
     $//<![CDATA[ \begin{array}{l}G_0\end{array} //]]>$ is taken from Small_Strain_Shear_Modulus_2.

This correlation of $//<![CDATA[ \begin{array}{l}E_0\end{array} //]]>$ is applicable to all soil types.

Young's Modulus 2

Young's Modulus 2 ($//<![CDATA[ \begin{array}{l}E_0\end{array} //]]>$) in Youngs_Modulus_2 is defined as:

$$//<![CDATA[ \begin{array}{l}\displaystyle E_0= \alpha q_c\end{array} //]]>$$

CPT in Geotechnical Practice p 160, Figure 6.13

Where:
     $//<![CDATA[ \begin{array}{l}\alpha\end{array} //]]>$ is calculated from degree of loading, $//<![CDATA[ \begin{array}{l}q_c\end{array} //]]>$, effective stress and reduction factor as given in the following plot.