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Retaining wall design software

Describe the wall. Rischio builds it, calculates it, and shows its work.

Cantilever, gravity and gabion walls, checked for overturning, sliding, bearing capacity and eccentricity, with the calculation report ready to hand in. Describe your wall to the agent, or enter it yourself.

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What it checks.

Every check with its rule and its limit, Rischio's defaults. In the studio, each result opens into its equation, with your numbers in it.

How it calculates, step by step
CheckLimit

Overturning

The wall rotating about its toe

FS=ΣMRΣMOFS = \frac{\Sigma M_R}{\Sigma M_O}

≥2.0\ge 2.0

Sliding

The wall pushed along its base

FS=RΣHFS = \frac{R}{\Sigma H}

≥1.5\ge 1.5

Bearing capacity

The ground under the base giving way

FS=quqmaxFS = \frac{q_u}{q_{max}}

≥3.0\ge 3.0

Eccentricity

The resultant inside the middle third of the base

ee

≤B6\le \frac{B}{6}

Gabion levels

Each level overturning or sliding on the one below

FS=ΣMRΣMO,  RΣHFS = \frac{\Sigma M_R}{\Sigma M_O},\; \frac{R}{\Sigma H}

≥2.0,  ≥1.5\ge 2.0,\; \ge 1.5

What you can model

  • Cantilever, gravity, L and T walls
  • Gabion walls in stepped levels
  • Up to 20 parts, each with its batter
  • Layered backfill and foundation
  • Sloping backfill
  • Water behind and in front
  • Uniform surcharges
  • Embedment in front of the toe

How it's calculated

  • Rankine earth pressure on the virtual back: active behind, passive in front when the wall is embedded
  • Cohesive backfill with its tension crack, full of water
  • Hydrostatic thrust on both sides, and uplift under the base
  • Bearing capacity by the general equation, on the effective width

The calculation report, ready to sign.

This is the one for the model the editor opens on, as the studio makes it. Read through it.

  • The checks' summary first, each with its margin
  • Every section with its equations and the values they take
  • The assumptions and warnings at the end, no small print

As PDF and Word, with your letterhead, in Professional.

Your engineering firmYour address · your license number

Calculation report

Model
Cantilever retaining wall
Analysis
Retaining wall
Date
15 October 2026
Units
SI · kN, m, kPa

1Summary

The model satisfies all 4 checks.

CheckValueLimitMarginResult
Overturning3.15 ≥ 2.00 +57 %OK
Sliding1.95 ≥ 1.50 +30 %OK
Bearing capacity3.78 ≥ 3.00 +26 %OK
Eccentricity0.243 m≤ 0.600 m+59 %OK

Limits are Rischio's defaults.

2Model

Figure 1. Section of the model.

Structure

WallWall

Material Concrete
Unit weight γ\gamma24.00 kN/m³
Embedment depth DD1.20 m
ShapexxmHHmBBmb1b_1mb2b_2mω\omega°
StemTrapezoid0.6005.40—0.6000.3000.000
FootingRectangle0.0000.6003.60———

xx Position from the toe · HH Height · BB Width · b1b_1 Bottom width · b2b_2 Top width · ω\omega Back face batter

Backfill

Ground surfaceBackfill

Backfill slope β\beta20.00 °
ttmγ\gammakN/m³c′c'kPaφ′\varphi'°
Granular fill6.0018.500.00035.00

tt Thickness · γ\gamma Unit weight · c′c' Cohesion · φ′\varphi' Friction angle

Foundation

γ\gammakN/m³c′c'kPaφ′\varphi'°
Silty sand18.5010.0030.00

γ\gamma Unit weight · c′c' Cohesion · φ′\varphi' Friction angle

3Geometry and weights

Weight of Footing

W=A⋅γc=51.84  kN/m\begin{aligned} W &= A \cdot \gamma_c \\ &= 51.84\;\text{kN/m} \end{aligned}

where AA = 2.16 m²

Weight of Stem

W=A⋅γc=58.32  kN/m\begin{aligned} W &= A \cdot \gamma_c \\ &= 58.32\;\text{kN/m} \end{aligned}

where AA = 2.43 m²

Weight of the soil over the heel

Ws=ΣAiγi(γsat below the water table)=259.2  kN/m\begin{aligned} W_s &= \Sigma A_i \gamma_i \quad (\gamma_{sat} \text{ below the water table}) \\ &= 259.2\;\text{kN/m} \end{aligned}

Base width

BB = 3.60 m

4Earth pressure

θ = 54.2°40.9 kPa
Figure 2. Earth and water pressure on the virtual back, and the active failure wedge behind it with its slip plane at θ.

Height of the virtual back

H′ (height of the virtual back at the heel)=6.87  m\begin{aligned} &H' \text{ (height of the virtual back at the heel)} \\ &= 6.87\;\text{m} \end{aligned}

Active thrust, horizontal

Pa,h=∫0H′[(σv′+q)Ka−2cKa]+dz⋅cos⁡β=132.1  kN/m\begin{aligned} P_{a,h} &= \int_0^{H'} \left[ (\sigma'_v + q) K_a - 2c\sqrt{K_a} \right]^+ dz \cdot \cos\beta \\ &= 132.1\;\text{kN/m} \end{aligned}

where qq = 0.000 kPa, H′H' = 6.87 m

Active thrust, vertical

Pa,v=∫0H′σa dz⋅sin⁡β=48.08  kN/m\begin{aligned} P_{a,v} &= \int_0^{H'} \sigma_a \, dz \cdot \sin\beta \\ &= 48.08\;\text{kN/m} \end{aligned}

Passive resistance

Pp=∫0Dfσp dz=81.53  kN/m\begin{aligned} P_p &= \int_0^{D_f} \sigma_p \, dz \\ &= 81.53\;\text{kN/m} \end{aligned}

5Overturning

Resisting moment

ΣMR=ΣWixi+Wsxs+Pa,vB=952.5  kN⋅m/m\begin{aligned} \Sigma M_R &= \Sigma W_i x_i + W_s x_s + P_{a,v} B \\ &= 952.5\;\text{kN·m/m} \end{aligned}

where WstemW_{stem} = 58.32 kN/m, xstemx_{stem} = 0.967 m, WfootingW_{footing} = 51.84 kN/m, xfootingx_{footing} = 1.80 m, WsW_s = 259.2 kN/m, xsx_s = 2.43 m, Pa,vP_{a,v} = 48.08 kN/m, BB = 3.60 m

Overturning moment

ΣMO=Pa,h ya+Pw yw+Pwc ywc+UxU=302.6  kN⋅m/m\begin{aligned} \Sigma M_O &= P_{a,h} \, y_a + P_w \, y_w + P_{wc} \, y_{wc} + U x_U \\ &= 302.6\;\text{kN·m/m} \end{aligned}

where Pa,hP_{a,h} = 132.1 kN/m, yay_a = 2.29 m, PwP_w = 0.000 kN/m, ywy_w = 0.000 m, PwcP_{wc} = 0.000 kN/m, ywcy_{wc} = 6.87 m, UU = 0.000 kN/m, xUx_U = 0.000 m

Check · Overturning

FS=ΣMRΣMO=3.15   ≥2.00 \begin{aligned} FS &= \frac{\Sigma M_R}{\Sigma M_O} \\ &= 3.15\,\text{} \; \ge 2.00\,\text{} \end{aligned}

margin +57 %

where ΣMR\Sigma M_R = 952.5 kN·m/m, ΣMO\Sigma M_O = 302.6 kN·m/m

OK

6Sliding

Total vertical force

ΣV=ΣWi+Ws+Pa,v−U=417.4  kN/m\begin{aligned} \Sigma V &= \Sigma W_i + W_s + P_{a,v} - U \\ &= 417.4\;\text{kN/m} \end{aligned}

where WstemW_{stem} = 58.32 kN/m, WfootingW_{footing} = 51.84 kN/m, WsW_s = 259.2 kN/m, Pa,vP_{a,v} = 48.08 kN/m, UU = 0.000 kN/m

Total horizontal force

ΣH=Pa,h+Pw+Pwc=132.1  kN/m\begin{aligned} \Sigma H &= P_{a,h} + P_w + P_{wc} \\ &= 132.1\;\text{kN/m} \end{aligned}

where Pa,hP_{a,h} = 132.1 kN/m, PwP_w = 0.000 kN/m, PwcP_{wc} = 0.000 kN/m

Friction angle at the base

δ=23ϕ=20.00  °\begin{aligned} \delta &= \tfrac{2}{3} \phi \\ &= 20.00\;\text{°} \end{aligned}

Adhesion at the base

ca=23c=6.67  kPa\begin{aligned} c_a &= \tfrac{2}{3} c \\ &= 6.67\;\text{kPa} \end{aligned}

Resistance to sliding

R=ΣVtan⁡δ+B ca+Pp=257.4  kN/m\begin{aligned} R &= \Sigma V \tan\delta + B \, c_a + P_p \\ &= 257.4\;\text{kN/m} \end{aligned}

where ΣV\Sigma V = 417.4 kN/m, δ\delta = 20.00 °, BB = 3.60 m, cac_a = 6.67 kPa, PpP_p = 81.53 kN/m

Check · Sliding

FS=RΣH=1.95   ≥1.50 \begin{aligned} FS &= \frac{R}{\Sigma H} \\ &= 1.95\,\text{} \; \ge 1.50\,\text{} \end{aligned}

margin +30 %

where RR = 257.4 kN/m, ΣH\Sigma H = 132.1 kN/m

OK

7Bearing capacity

162.9 kPa69.0 kPa
Figure 3. Contact pressure under the base.

Eccentricity of the resultant

e=∣B2−ΣMR−ΣMOΣV∣=0.243  m\begin{aligned} e &= \left| \frac{B}{2} - \frac{\Sigma M_R - \Sigma M_O}{\Sigma V} \right| \\ &= 0.243\;\text{m} \end{aligned}

where BB = 3.60 m, ΣMR\Sigma M_R = 952.5 kN·m/m, ΣMO\Sigma M_O = 302.6 kN·m/m, ΣV\Sigma V = 417.4 kN/m

Maximum contact pressure

qmax=ΣVB(1+6eB)=162.9  kPa\begin{aligned} q_{max} &= \frac{\Sigma V}{B} \left(1 + \frac{6e}{B}\right) \\ &= 162.9\;\text{kPa} \end{aligned}

where ΣV\Sigma V = 417.4 kN/m, BB = 3.60 m, ee = 0.243 m

Minimum contact pressure

qmin=ΣVB(1−6eB)=68.97  kPa\begin{aligned} q_{min} &= \frac{\Sigma V}{B} \left(1 - \frac{6e}{B}\right) \\ &= 68.97\;\text{kPa} \end{aligned}

where ΣV\Sigma V = 417.4 kN/m, BB = 3.60 m, ee = 0.243 m

Effective width

B′=B−2e=3.11  m\begin{aligned} B' &= B - 2e \\ &= 3.11\;\text{m} \end{aligned}

where BB = 3.60 m, ee = 0.243 m

Overburden at the base

q=σv′(Df)=22.20  kPa\begin{aligned} q &= \sigma'_v(D_f) \\ &= 22.20\;\text{kPa} \end{aligned}

Effective unit weight under the base

γ′\gamma' = 18.50 kN/m³

Ultimate bearing capacity

qu=cNcFcsFcdFci+qNqFqsFqdFqi+12γ′B′NγFγsFγdFγi=616.2  kPa\begin{aligned} q_u &= c N_c F_{cs} F_{cd} F_{ci} + q N_q F_{qs} F_{qd} F_{qi} + \tfrac{1}{2} \gamma' B' N_\gamma F_{\gamma s} F_{\gamma d} F_{\gamma i} \\ &= 616.2\;\text{kPa} \end{aligned}

where qq = 22.20 kPa, γ′\gamma' = 18.50 kN/m³, B′B' = 3.11 m, NcN_c = 30.14 , NqN_q = 18.40 , NγN_\gamma = 22.40 , FcsF_{cs} = 1.00 , FqsF_{qs} = 1.00 , FγsF_{\gamma s} = 1.00 , FcdF_{cd} = 1.10 , FqdF_{qd} = 1.10 , FγdF_{\gamma d} = 1.00 , FciF_{ci} = 0.648 , FqiF_{qi} = 0.648 , FγiF_{\gamma i} = 0.172

Check · Bearing capacity

FS=quqmax=3.78   ≥3.00 \begin{aligned} FS &= \frac{q_u}{q_{max}} \\ &= 3.78\,\text{} \; \ge 3.00\,\text{} \end{aligned}

margin +26 %

where quq_u = 616.2 kPa, qmaxq_{max} = 162.9 kPa

OK

8Eccentricity

Check · Eccentricity

e≤B6e=0.243 m  ≤0.600 m\begin{aligned} e &\le \frac{B}{6} \\ e &= 0.243\,\text{m} \; \le 0.600\,\text{m} \end{aligned}

margin +59 %

where ee = 0.243 m, BB = 3.60 m

OK

9Notes

  1. The sliding resistance includes 81.5 kN/m of passive resistance in front of the wall; without it, FS\mathrm{FS} = 1.33. Ensure this soil cannot be excavated or eroded.

Validated against recognized references.

Rischio is checked against worked examples from recognized engineering references. The same inputs give the same answers, and where they differ, it says why.

ExampleReferenceRischioDifference
Cantilever wall →
Overturning2.982.980.0 %
Sliding2.732.73−0.1 %
Bearing capacity3.02.93−2.3 %
Gravity wall →
Overturning3.043.040.0 %
Sliding3.053.04−0.2 %
Maximum contact pressure174.24 kPa174.13 kPa−0.1 %
Minimum contact pressure42.86 kPa42.89 kPa+0.1 %

Learn more.

Questions, answered.

Which walls can it check?

Cantilever, gravity, L and T walls of concrete or masonry, built from up to 20 rectangular or trapezoidal parts, and gabion walls in stepped levels.

Which safety factors does it use?

Overturning ≥ 2.0, sliding ≥ 1.5, bearing capacity ≥ 3.0, and the resultant inside the middle third (e ≤ B/6). They are Rischio's defaults; every result shows its margin, so you can judge it against the factor your code asks for.

How is the earth pressure calculated?

With Rankine's theory, on the virtual back through the heel: active behind the wall, and passive in front of the toe when the wall is embedded. It takes a sloping backfill, layered soils and cohesion; in a cohesive backfill the tension crack is taken full of water.

Does it include earthquake loads?

Not yet. It checks static loads: the earth pressure, the water and uniform surcharges.

Does it design the reinforcement?

No. It checks the wall's external stability: overturning, sliding, bearing and eccentricity. The structural design of the stem and the footing, and the global stability of the slope, are outside it.

What does the agent do, and what does the engine do?

The agent turns your words into a model and edits it. The engine, the same one behind the editor, does every calculation: no number comes from the agent. You review the model, open every equation and sign the report.

Is it free?

The Free plan has all four tools and up to 3 models. Professional, $49 a month, adds unlimited models, the report as PDF and Word with your letterhead, and your own agent through MCP. Every account starts with 14 days of Professional, no card needed.

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