Retaining Wall Calculator
Calculate lateral earth pressure, overturning moment, and sliding resistance for retaining walls. Check stability factors of safety.
Enter wall parameters to check stability
IMPORTANT DISCLAIMER
This calculator provides PRELIMINARY ESTIMATES ONLY and is intended for planning and budgeting purposes. Results should NOT be used for final structural design or construction without verification by a licensed Professional Engineer (PE) or Chartered Engineer (CEng).
By using this tool, you acknowledge that:
1. All calculations are indicative and may not account for site-specific conditions, load combinations, or local code requirements.
About This Calculator
The Retaining Wall Calculator gives contractors and engineers a quick preliminary check of a cantilever retaining wall. It calculates Rankine active earth pressure, including a uniform surcharge, and checks overturning and sliding against a factor of safety of 1.5 using simplified assumptions. It does not check bearing pressure, water pressure or structural capacity, so it is a starting point for discussion with your structural engineer, not a design.
When to Use This Calculator
- Designing basement retaining walls for buildings
- Sizing gravity walls for road embankments
- Checking stability of cantilever retaining walls
- Preliminary design for tender submissions
- Verifying existing wall adequacy for additional loads
How to Use This Calculator
Define Wall Geometry
Enter wall height, base width, toe length, heel length, and stem thickness.
Input Soil Properties
Specify unit weight, friction angle (φ), cohesion (c), and backfill slope if any.
Add Surcharge Loads
Include any uniform or point loads on the backfill (traffic, building loads).
Check Stability
Verify factors of safety for overturning (≥2.0), sliding (≥1.5), and bearing (≥3.0).
Review Design
Get earth pressure diagram, moment/shear at key sections, and reinforcement guidance.
Typical Scenarios in UAE & Gulf Projects
Retained height 3 m, soil 18 kN/m³ with φ = 30°, 10 kN/m² surcharge, 2.4 m base and 0.3 m stem. The calculator gives Ka = 0.333, a total horizontal force of 37 kN/m and an overturning moment of 42 kNm/m. Overturning (1.11) and sliding (0.53) fall below 1.5, so the result is Needs Review: the engineer would add the soil on the heel and consider a shear key before sizing the wall.
Retained height 2 m, soil 19 kN/m³ with φ = 32°, 5 kN/m² surcharge, 1.6 m base and 0.25 m stem. Overturning passes at 1.73, but sliding is 0.80, so the calculator recommends a shear key or more base friction. A quick way to see which check governs before the detailed design.
Calculation Methodology
Earth Pressure
The active earth pressure coefficient uses Rankine's formula Ka = (1 − sin φ) / (1 + sin φ). The soil thrust is ½·Ka·γ·H² acting at H/3 above the base, and a uniform surcharge q adds Ka·q·H acting at H/2. The pressure shown at the base is Ka·γ·H + Ka·q.
Stability Checks
The wall weight uses concrete at 24 kN/m³: an assumed 0.3 m thick base of the width you enter, plus the stem (stem width × H). Overturning factor of safety = wall weight × half the base width ÷ overturning moment. Sliding factor of safety = 0.5 × wall weight ÷ total horizontal force. Both must be at least 1.5 for an OK result.
Simplifications and Limits
The weight of soil on the heel, passive resistance at the toe, water pressure, sloping backfill, wall friction and bearing pressure are not included, and the resisting moment assumes the wall's weight acts at the centre of the base. Use the result as a preliminary check only; a retaining wall must be designed by a qualified engineer (for example to BS 8002 or Eurocode 7).
Frequently Asked Questions
Take Your Calculations Further
This calculator reflects the logic built into Arkan's construction management platform.
Last Updated: October 2026
Standards Reference: Rankine active pressure with simplified stability checks. Full design: BS 8002, Eurocode 7