How to use the shoring earth pressure calculator
The first number a shoring check needs is the pressure resultant on one foot of wall. Enter the wall height, the soil unit weight and your active and passive coefficients and both resultants appear with their moments and with the resisting moment divided by the overturning moment.
The relations applied are the integrals of a triangular pressure distribution: the active resultant is 0.5 x Ka x unit weight x height squared, the passive resultant is 0.5 x Kp x unit weight x height squared, and in both cases the lever arm is one third of the height above the base. Height goes in feet and unit weight in pounds per cubic foot (pcf); the page converts them to SI internally and shows the base pressure in psf, the resultants in lb per foot of wall and the moments in lb·ft per foot, each with the SI value in parentheses. Because the lever arm is shared and passive pressure is taken over the full wall height, the moment ratio always equals Kp/Ka, whatever the height or unit weight. On a real shoring wall passive resistance only develops over the embedded length below the excavation, and this calculator does not model embedment depth, so the ratio is a coefficient comparison and not the overturning safety factor of an actual design. A separate warning appears when the ratio is below 1. Values are as of October 2026.
Pressure coefficients, unit weights and required safety factors change with ground conditions and with the standard applied and were not confirmed in an authoritative source, so no values are suggested and all of them are entered by you. Embedment depth, sliding, surcharge and cohesion, groundwater and strut reactions are not covered. This calculator is for reference and does not replace design. Review by a qualified engineer is required.
Frequently asked questions
The active and passive coefficients taken from your soil report or the standard you apply. Deriving them from the friction angle is not covered.
Because both pressures act over the same height with the same lever arm and embedment depth is not modeled. The ratio therefore is always Kp/Ka and is not the overturning safety factor of an actual design.
Embedment depth and sliding are not covered. This page stops at the active and passive resultants, their moments and the overturning factor.