EFP: The program does not alter the magnitude of the applied active pressure to account for the sloping backfill.
Rankine: The Rankine equation includes the effects of backfill slope when calculating the active pressure.
Coulomb: The Coulomb equation includes the effects of backfill slope when calculating the active pressure.
EFP: The program uses the height of soil that occurs at the end of the heel.
Rankine: The program uses the height of soil that occurs at the end of the heel.
Coulomb: The program uses the height of soil that occurs at the end of the heel.
EFP: Vertical component is only calculated when the soil slope is non-zero. To calculate the vertical component, the program uses the Rankine equation to back-calculate the angle of internal friction using soil slope, soil density and the user-entered equivalent fluid pressure (Ka). From that angle it calculates the vertical component as tan(angle) * Ka.
Rankine: The active force acts at the angle specified for the sloping backfill.
Coulomb: The active force acts at phi/2 measured from the soil-surface of the wall.
EFP: The vertical component is applied at the back of the heel when user selects to include it.
Rankine: The vertical component is applied at the back of the heel when user selects to include it.
Coulomb: The vertical component is applied at the back of the heel when user selects to include it.
EFP: The user must adjust the magnitude of the EFP.
Rankine: No additional action is required on the part of the user.
Coulomb: No additional action is required on the part of the user.