GGU-RETAIN: Active earth pressure

Active earth pressure is analysed to DIN 4085. DIN 4085 provides two relationships for the coefficients of earth pressure k_ah (friction) and k_ch (cohesion). Alternatively, there is the option of determining the cohesion coefficient from k_ch = k_ah^-2, a method often found in older literature.

In addition, calculation of the active earth pressure after Culmann is possible. The calculations use a slice method with planar slip surfaces.