



Calculate Driving Wedge Force and Overturning Moment: 
Use the calculation below to calculate the driving wedge force resultant and
overturning moment for a noncohesive or cohesive backfill with or without a
surcharge. 

Calculation: 

Designer/Checker: 



Input: 




(Note: All input Metric units are converted to English units
for the equations below and then the output English units are converted back to
Metric) 

The following calculation will calculate the driving wedge forces on a retaining
wall. Conservative wedge loading can be calculated for cohesive
soils by setting cd = 0.0 and dc = 0.0. 
This assumption does not take into account the reduced wedge resulting from
cohesive soils and therefore will derive a larger horizontal resultant load on
the wall. 

Angle of backfill slope, (AngB  degrees) 

Slip Plane Angle, (SPAng  deg) 

Depth of crack, (dc  ft or m) 

Height of retaining wall or wedge (H  ft or m) 

Density of soil (d  pcf or kg/m^3) 

Developed angle of internal friction (AIFd  degrees) 

*AIFd = Arctan(SMF * tan AIF) 

Cohesion of the soil * SMF (cd  psf or kPa) 

Strip surcharge (V  lb/ft or N/m) 

Distance to strip surcharge (x1  ft or m) 

Horizontal width of strip surcharge (x2  ft or m) 

Typically the Strength Mobilization Factor (SMF) is 2/3 











Output: 

Login to enable the Formulas!

Resultant Surcharge Force, Rv = 

Distance Y where Rv occurs on wall (Yv) = 

Resultant Soil Force, Rd = 

Distance Y where Rd occurs on wall (Yd) = 

Total Lateral Resultant Force, Ra = Rv + Rd = 

Overturning Moment, Ma = Rd(Yd) + Rv(Yv) = 

Check if V < Vmax: Vmax = 

If V > Vmax,


SPAng = Abs(Atan((hdc+(x1+x2/2)tanAngB)/(x1+x2/2)))= 






