The coefficient of at-rest earth pressure, k0 , is obtained after FRANKE (Die Bautechnik 1974/No. 1) from:
The vertical load component resulting from wall friction is obtained from the tangent of the angle of wall friction. However, in accordance with the EAB, a minimum value of 0.5 · the horizontal component is assumed when the tangent of the angle of wall friction is < 0.5.