====== Sforzo normale ======


$$\boldsymbol{\sigma} = 
\begin{Bmatrix} 
\sigma_x \\\\
\sigma_y \\\\
\sigma_z \\\\
\tau_{xy} \\\\
\tau_{xz} \\\\
\tau_{yz}
\end{Bmatrix} = 
\begin{Bmatrix} 
\lambda \\\\
0 \\\\
0 \\\\
0 \\\\
0 \\\\
0
\end{Bmatrix}$$

$$\boldsymbol{\varepsilon} = 
\begin{Bmatrix} 
\varepsilon_x \\\\
\varepsilon_y \\\\
\varepsilon_z \\\\
\gamma_{xy} \\\\
\gamma_{xz} \\\\
\gamma_{yz}
\end{Bmatrix} = 
\begin{Bmatrix} 
\frac{\lambda}{E} \\\\
-\frac{\nu \, \lambda}{E} \\\\
-\frac{\nu \, \lambda}{E} \\\\
0 \\\\
0 \\\\
0
\end{Bmatrix}$$