Retaining Wall Design Calculator
Design cantilever retaining walls with full stability analysis, structural member design, and reinforcement detailing — all in one integrated, browser-based calculator.
Calculator Features
Comprehensive retaining wall analysis covering geotechnical stability, structural design, and reinforcement detailing.
Cantilever Retaining Wall Design
Full geometry definition for stem, toe, and heel with variable thickness and key dimensions.
Rankine Active/Passive Earth Pressure
Automatic calculation of Ka and Kp coefficients from soil friction angle and wall inclination.
Overturning Stability (FOS ≥ 2.0)
Moment equilibrium check about the toe with clear pass/fail indicator and factor of safety output.
Sliding Stability (FOS ≥ 1.5)
Horizontal force equilibrium including base friction and passive resistance with shear key option.
Bearing Pressure Check
Trapezoidal or triangular pressure distribution under the base slab compared to allowable bearing capacity.
Settlement Analysis (Subgrade Modulus)
Estimate differential and total settlement using subgrade reaction modulus for serviceability check.
Tension Zone Check
Verifies the resultant stays within the middle third of the base to avoid uplift and soil separation.
Water Table on Active Side
Accounts for hydrostatic pressure and buoyancy when the water table is within the retained soil.
Surcharge & Line Load
Apply uniform surcharge and/or concentrated line loads on the backfill with automatic pressure integration.
Wall Stem Flexure & Shear Design
Ultimate moment and shear at critical sections with required reinforcement per ACI 318-19M.
Toe Slab Design
Bending moment and shear from net upward soil pressure under the toe with reinforcement output.
Heel Slab Design
Design for net downward loading from retained soil weight minus upward bearing pressure.
Reinforcement Summary (As mm²/m)
Clear tabular output of required steel area per metre for every element of the retaining wall.
Interactive Section & Plan View Graphics
Dynamic SVG diagrams showing wall geometry, pressure distribution, and reinforcement layout.
Step-by-Step Calculation Sheet
Full transparent calculation with formulas and intermediate values — ready for engineering review.
PDF Export
One-click export of the full design report including geometry, loads, analysis, and reinforcement details.
How It Works
Four simple steps from geometry definition to a complete, exportable design report.
Define Geometry & Soil
Enter wall dimensions, retained height, soil unit weight, friction angle, and bearing capacity.
Enter Loads
Specify surcharge, line loads, water table level, and any additional applied forces.
Check Stability & Design
Review overturning, sliding, bearing, settlement, and full reinforcement design instantly.
Export PDF
Download the complete calculation sheet with diagrams, tables, and reinforcement summary.