Steel U-Shaped Sheet Pile Profile

This page demonstrates how to create and visualize U-shaped sheet pile profiles using the Blueprints library. U-shaped sheet piles are interlocking structural elements used in retaining walls and cofferdams. The PU, PAU, PAL, AU and GU series are standardized families of U-shaped sheet piles available in Blueprints.

We will:

Create, plot and inspect the section properties of a standard PU profile
Combine several interlocking sheets into a wall
Apply a corrosion allowance
Use a standard GU sheet pile
Define a fully custom U-shaped sheet pile from raw coordinates

1. Create a Standard PU Profile

The standard PU sheet pile profiles are available from the standard_profiles module. Access one of the predefined profiles as a class attribute, for example PU18. This returns a SheetpileUProfile instance representing a single sheet.

from blueprints.structural_sections.steel.standard_profiles import PU

pu_profile = PU.PU18
print(f"Profile name: {pu_profile.name}")
print(f"Web thickness: {pu_profile.web_thickness} mm")
print(f"Flange thickness: {pu_profile.flange_thickness} mm")
print(f"Interlocking distance (center-to-center): {pu_profile.interlocking_ctc} mm")

Profile name: PU 18
Web thickness: 9.0 mm
Flange thickness: 11.2 mm
Interlocking distance (center-to-center): 600 mm

2. Plot the Single Sheet

Generate a plot of the profile using the plot() method to verify its geometry.

fig = pu_profile.plot(show=False)  # use show=True locally to open the plot directly

3. Access the Section Properties

Retrieve the section properties (area, perimeter, moments of inertia, section moduli, etc.) of the single sheet using the section_properties() method.

properties = pu_profile.section_properties()
print(f"Area: {properties.area:.1f} mm²")
print(f"Perimeter: {properties.perimeter:.1f} mm")
print(f"Second moment of area about x-axis (ixx_c): {properties.ixx_c:.0f} mm⁴")
print(f"Section modulus (zxx_plus): {properties.zxx_plus:.0f} mm³")

Area: 9797.4 mm²
Perimeter: 1935.9 mm
Second moment of area about x-axis (ixx_c): 72270721 mm⁴
Section modulus (zxx_plus): 484646 mm³

4. Build a Wall from Multiple Interlocking Sheets

Sheet piles are installed side by side to form a continuous wall. Use the multiple_sheets() method to create a new profile made up of several interlocking sheets. Every second sheet is automatically mirrored and connected at the interlock, matching how the sheets snap together on site. At each interlock a small connector element is drawn between adjacent sheets to represent the clutch where the two sheets lock together, alternating between the top and bottom of the wall.

pu_wall = pu_profile.multiple_sheets(number_of_sheets=4)
fig = pu_wall.plot(show=False)

5. Apply a Corrosion Allowance (optional)

Sheet piles in aggressive environments lose material over their design life. Use with_corrosion() to reduce the wall thickness on both faces by the given amount. The web and flange thicknesses are each reduced by twice the corrosion value (corrosion acts on both sides).

pu_corroded = pu_profile.with_corrosion(corrosion=1.0)
fig = pu_corroded.plot(show=False)

6. Use a Standard GU Sheet Pile (optional)

The GU series is another standardized family of U-shaped sheet piles. Access them just like the PU profiles from the standard_profiles module. Each GU profile is a SheetpileUProfile and supports the same plot(), section_properties(), multiple_sheets() and with_corrosion() methods shown above.

from blueprints.structural_sections.steel.standard_profiles import GU

gu_profile = GU.GU18N
print(f"Profile name: {gu_profile.name}")
print(f"Interlocking distance (center-to-center): {gu_profile.interlocking_ctc} mm")

Profile name: GU 18N
Interlocking distance (center-to-center): 600 mm

fig = gu_profile.plot(show=False)

7. Define a Custom U-Shaped Sheet Pile (optional)

When a profile is not part of the standard database, you can build one directly from its outline coordinates using SheetpileUProfile. Provide the (x, y) coordinates of the single-sheet outline together with the web thickness, flange thickness and the center-to-center interlocking distance. The custom profile supports the same plot(), section_properties(), multiple_sheets() and with_corrosion() methods as the standard profiles.

from blueprints.structural_sections.steel.profile_definitions.sheetpile_u_profile import SheetpileUProfile

custom_u_profile = SheetpileUProfile(
    coordinates=list(PU.PU18.coordinates),  # replace with your own outline
    web_thickness=9.5,  # mm
    flange_thickness=9.5,  # mm
    interlocking_ctc=630,  # mm (center-to-center distance between sheets)
    name="Custom U-Profile",
)
fig = custom_u_profile.plot(show=False)