Young's Modulus

Young's Modulus 1

Small Strain Young's Modulus 1 ($\begin{array}{l}E_0\end{array}$) in Youngs_Modulus_1 is defined as:

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

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

This correlation of $\begin{array}{l}E_0\end{array}$ is applicable to all soil types.

Young's Modulus 2

Young's Modulus 2 ($\begin{array}{l}E_0\end{array}$) in Youngs_Modulus_2 is defined as:

CPT in Geotechnical Practice p 160, Figure 6.13

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