Reinforced soil wall (geogrid) calculator

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Worked example — results

• ✓ Sliding FS ≥ 1.5
• ✓ Overturning FS ≥ 2
• ✓ e ≤ L/6
• ✓ Bearing ≤ allowable
• ✓ Tension FS ≥ 1.0 (LTDS already factored)
• ✓ Pull-out FS ≥ 1.5

Method, formulas and assumptions

• Retained thrust Pa = ½KaγH² + KaqH acting on the back of the reinforced block
• Sliding: (W + qL)tanφ / (Pa + Pq); overturning about the toe
• Meyerhof: q = V/(L − 2e)
• Internal: T = Kar·σv·Sv; resisting length beyond the Rankine plane Le = L − (H − z)tan(45 − φ/2); pull-out = 2·Le·σv·tanφ·Ci
• AS 4678 uses partial factors on materials and loads: this FS-based check is preliminary

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