Cantilever Soldier Pile Design - Review Options in DeepEX Software

Cantilever soldier pile design requires that we determine the soldier pile embedment, size, and estimate lateral wall displacements. Cantilever soldier piles are feasible only if we do not encounter any groundwater above the final excavation subgrade. Dewatering might be required if groundwater is encountered above the excavation subgrade.

Cantilever soldier pile walls are commonly used when excavation depths are limited to 5m or less (15ft). In most cases, cantilever depths are kept to under 3.5m (10ft) because controlling wall displacements requires an increasingly stiffer steel section. In rare cases cantilever excavations can reach up to 6.5m (20ft) when good soils are encountered, and stiffer soldier piles are used.

The most common way of designing cantilever walls is by using the free earth method. In this approach, we need to calculate the point where moment equilibrium is achieved below the excavation. Typically, engineers assume active lateral earth pressures on the driving side and passive lateral earth pressures on the resisting side. With soldier pile walls, we can account for 3-dimensional pile spacing effects by adjusting lateral soil pressures with the flange or drilled pile diameter size below the excavation.

Cantilever soldier pile design


Figure 1: Cantilever soldier pile wall analysis with DeepEX deep excavation software

Because the free earth method balances out only moments and not wall shears there are general recommendations for increasing the calculated wall embedment by 20 to 40% to achieve a real safety factor of 1.0. Additional safety factors must be applied beyond by increasing the provided wall embedment by at least 25%.

The free earth method can produce excessive lateral wall displacements. For this reason, certain transportation authorities recommend adjusting displacements by assuming a virtual fixity point at 25% of the required embedment for achieving moment equilibrium. While there is little theoretical justification, such an adjustment appears to produce much more reasonable wall displacement results that are close to actual measured wall displacements.

When using steel beams, the structural section modulus will be determined by assuming an allowable yield stress of 0.6 Fy (where Fy is the yield strength of the steel). In a simplified approach the steel section modulus can then determined as Sxx = Mmax/0.6 Fy. With reinforced concrete walls a safety factor of 1.5 is commonly used when a service design is performed.

Arching effects for cantilever soldier piles in DeepEX software

Figure 2: Arching effects for cantilever soldier pile walls in DeepEX deep excavation software


Cantilver soldier piles in virtual reality with DeepEX software

Figure 3: With DeepEX and HoloDeepEX you can see soldier pile walls in virtual reality

DeepEX Software Can Design any Deep Excavation Model in Minutes!

Analyze Deep Excavations with All Methods: Limit Equilibrium - Non-Linear - Finite Element Analysis!

Design Anchored Walls, Braced Excavations, Cofferdams, Deadman Wall Systems, Top-Down + more!

AASHTO LRFD, CALTRANS, EUROCODES 2, 3, 7, 8, ACI, BS, Australian Codes, Chinese Codes +more!

Review DeepEX Capabilities

Solutions for Geotechnical Engineering Professionals:




Learn More



Pile Foundations

Learn More



Helical Piles

Learn More



Soil Nail Walls

Learn More

Trusted By

1. Logo Arup.JPG
2. Logo Keller.JPG
3. Logo PBA.JPG
5. Logo Hatch.JPG
6. Logo Mottmac.JPG
7. Logo Jacobs.JPG
8. Logo GZA.JPG
9. Logo GarretFlaming.JPG
10. Logo Lavalin.JPG
11. Logo Magnusson Klem.JPG
12. Logo MoDOT.JPG
13. Logo URS.JPG
14. Logo Stalworth.JPG
15. Logo Kleinfelder.JPG
16. Logo Samsung.JPG
17. Logo Gepfreeze.JPG
19. Logo GulfConstruct.JPG
20. Logo Temeltas.JPG
21. Logo AttikoMetro.JPG
22. Logo Flatiron.JPG
23. Logo Kozaba.JPG
24. Logo Siefert.JPG
25. Logo AlGhuair.JPG
26. Logo Earthtech.JPG
27. Logo Russo.JPG
28. Logo Danbro.JPG
29. Logo Atkins.JPG
30. Logo LBFoster.JPG
31. Logo Dominion.JPG
32. Logo Acons.JPG
33. Logo NSCC.JPG
34. Logo Econstruct.JPG
35. Logo AUD.JPG
18. Logo Eptisa.JPG

      Deep Excavation LLC
    240 W 35th Street, Suite 1004
    New York, NY, 10001