RC Retaining Wall Design

CSA A23.3:24 · NBCC load combinations · Cantilever wall

Checks26/26

Pass

FOS overturning

4.14

FOS sliding

1.75

q max

104.31 kPa

Stem Mf / Mr

94.9 / 101.9

Crack z

24,000 N/mm

Deflection Δ

0.7 mm

Project information

Appears on the printed calculation sheet

ProjectProject numberRevisionDesigned byChecked byDate

Wall type & exposure

Cl. 14.1 — walls; Cl. 10.6.1 — crack control class

Wall typeExposure conditionCl. 10.6.1

z_maxCl. 10.6.1

25,000N/mm

Material properties

CSA A23.3:24 Cl. 8.4 · 8.5 · 8.6

f′c — concrete strengthCl. 8.6.1MPafy — rebar yieldCl. 8.5.1MPaEs — steel modulusCl. 8.5.3MPaγc — concrete unit weightCSA A23.1kN/m³ϕc — concrete factorCl. 8.4.2ϕs — steel factorCl. 8.4.3λ — density factor

α₁Eq. 10.1

0.805

0.85 − 0.0015·f′c ≥ 0.67

β₁Eq. 10.2

0.895

0.97 − 0.0025·f′c ≥ 0.67

frCl. 8.6.4

3.29MPa

0.6·λ·√f′c

EcCl. 8.6.2

26,621.22MPa

(3300√f′c + 6900)(γc/23)^1.5

7.513

Es / Ec

Wall geometry

Cl. 14.1.7 — minimum wall thickness 150 mm

H — total wall heightmHw — stem height above basemtw_top — stem thickness at topmtw_bot — stem thickness at baseCl. 14.1.7mDf — base slab thicknessmB — base slab widthmBtoe — toe projectionmDk — shear key depthmBk — shear key widthmcover — clear coverA23.1 T-17mmL — wall length along alignmentmJoint / counterfort spacingm

B_heel

2.000m

B − B_toe − tw_bot

H_total

4.000m

Hw + Df

d_stem

315.3mm

tw_bot − cover − db/2

d_base

415.3mm

Df − cover − db/2

Soil properties & loading

Rankine earth pressure coefficients

γs — retained soil unit weightkN/m³γs_f — front soil unit weightkN/m³φ — friction angle (°)δ — wall–soil friction (°)c — cohesionkPaq — surchargekPaq_allow — allowable bearingkPaDf_front — soil depth at toemGWL — depth below base (99 = none)mγw — water unit weightkN/m³

KaRankine

0.333

tan²(45 − φ/2)

KpRankine

3.000

tan²(45 + φ/2)

0.500

1 − sin φ

μ = tan δ

0.364

Load & resistance factors

NBCC Table 4.1.3.2 and geotechnical practice

αD — dead loadNBCC 4.1.3.2αD_min — favourable deadNBCC 4.1.3.2αE — earth pressureNBCC 4.1.3.2αL — live / surchargeNBCC 4.1.3.2FOS — overturningFOS — slidingFOS — bearing

Reinforcement selection

Bar areas from the CSA metric bar table

Stem vertical barStem vertical spacingCl. 14.1.8.2.3mmStem horizontal barStem horizontal spacingCl. 14.1.8.2.3mmBase barBase bar spacingCl. 7.4.1.2mmTransverse (stirrup) barStirrup spacing — stemCl. 11.3.8.1mmStirrup spacing — toeCl. 11.3.8.1mmStirrup spacing — heelCl. 11.3.8.1mm

As_prov = Ab × 1000 / spacing · stem 1500 mm²/m provided vs 984 mm²/m required (units shown here in mm²/m)