Longer side of the backfill area.

Symbol
$b_{\mathrm{y}}$
Unit
mm
Formulae
$\max\left(h_{\mathrm{b}}, w_{\mathrm{b}}\right)$
Related
$h_{\mathrm{b}}$
$w_{\mathrm{b}}$
Used in
$r_{\mathrm{b}}$