Global Steel Sheet Pile Size Standards Explained

You are working on an international project. The engineer is from Europe, the sheet piles will come from Asia, and the client is in the Middle East. You see designations like AZ 26¹, PZC 13, and U 400 x 125² on the same drawing. What do all these numbers mean?

Global steel sheet pile size standards vary by region. Europe uses EN 10248 with designations like U 400 x 125² for U piles and AZ 26¹ for Z piles. North America uses ASTM standards with designations like PZ 27 and PZC 13. Asia often uses the Type system (Type 2, Type 3, Type 4). Understanding these standards is essential for international projects.

I have supplied sheet piles to projects all over the world. The riverbank project in Southeast Asia used U 400 x 125² under EN 10248. A port project in the Middle East used AZ 26¹. A project in North America used PZC 13. Let me walk you through the different standards and how to compare them.

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What is the ASTM for sheet pile?

ASTM is the American standard for sheet piles. It covers several different specifications for different applications.

The main ASTM standards for sheet piles are ASTM A328¹ (carbon steel sheet piles), ASTM A572 Grade 50² (high-strength sheet piles), ASTM A690³ (marine grade sheet piles), and ASTM A857⁴ (cold-formed sheet piles). The dimensions and properties are defined by manufacturer data sheets that reference these standards.

ASTM Standards Overview

Let me explain the different ASTM standards and what they cover.

ASTM A328¹ – Carbon Steel Sheet Piles
This is the standard for standard carbon steel sheet piles. It specifies:

• Yield strength: 240 MPa (35 ksi) minimum
• Tensile strength: 410 MPa (60 ksi) minimum
• Chemical composition requirements
• Typical use: General retaining, temporary works, freshwater

ASTM A572 – High-Strength Low-Alloy Steel
This standard covers high-strength steel. Grade 50 is the most common for sheet piles:

• Yield strength: 345 MPa (50 ksi) minimum
• Tensile strength: 450 MPa (65 ksi) minimum
• Typical use: Deep excavations, heavy loads

ASTM A690³ – Marine Grade Sheet Piles
This is the standard for sheet piles with improved corrosion resistance in marine environments:

• Yield strength: 345 MPa (50 ksi) minimum
• Tensile strength: 485 MPa (70 ksi) minimum
• Contains copper, nickel, and phosphorus for corrosion resistance
• Typical use: Ports, harbors, seawalls

ASTM A857⁴ – Cold-Formed Sheet Piles
This standard covers light-gage cold-formed sheet piles:

• Yield strength: varies by thickness
• Typical use: Temporary works, light retaining

ASTM Sheet Pile Designations
ASTM standards do not specify dimensions. The dimensions come from manufacturer data sheets. Common North American designations include:

• PZ series: PZ 22, PZ 27, PZ 35, PZ 40 (hook-and-grip interlocks)
• PZC series: PZC 13, PZC 18, PZC 26, PZC 29 (ball-and-socket interlocks)
• U type: Various sections

My Experience
When a North American project calls for ASTM sheet piles, I ask which standard: A328, A572, or A690. Then I confirm the section (PZ, PZC, or U). The combination tells me exactly what to supply.

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What is the difference between U and Z sheet piles¹?

U and Z sheet piles¹ have different shapes, interlocks, and structural properties. The choice between them affects design, installation, and cost.

U sheet piles² are symmetric with interlocks at the neutral axis, making them easier to install and better for curved walls³. Z sheet piles¹ are asymmetric with interlocks at the outer flanges, giving them higher structural efficiency⁴ per kilogram of steel. U piles are designated by width and height (e.g., U 400 x 125). Z piles are designated by section modulus (e.g., AZ 26) or manufacturer codes (e.g., PZC 13).

Detailed Comparison

Let me break down the differences in detail.

U Type Sheet Piles

• Profile: Symmetric, looks like a U
• Interlock: Larssen ball-and-socket at neutral axis
• Width: Typically 400 mm or 600 mm
• Height: 100 mm to 210 mm
• Designation: Width x Height (U 400 x 125)
• Best for: Curved walls, moderate depths (under 10 m)
• Advantages: Easy installation, forgiving alignment, good water tightness

Z Type Sheet Piles

• Profile: Asymmetric, looks like a Z
• Interlock: Ball-and-socket or hook-and-grip at outer flanges
• Width: Typically 630 mm to 700 mm
• Height: 260 mm to 530 mm
• Designation: Section modulus (AZ 26) or manufacturer code (PZC 13)
• Best for: Deep, straight walls (over 10 m)
• Advantages: Higher strength per kg, wider sections, fewer piles

Comparison Table

Feature	U Type	Z Type
Symmetry	Symmetric	Asymmetric
Interlock position	Neutral axis	Outer flanges
Typical width	400-600 mm	630-700 mm
Typical height	100-210 mm	260-530 mm
Structural efficiency	Good	Higher
Curved walls	Excellent	Difficult
Straight walls	Good	Excellent
Installation	Forgiving	Requires more care
Designation	Width x Height	Section modulus or code

Regional Preferences

• Europe: Both U and Z are common. U for moderate depths, Z for deep excavations.
• North America: Z types (PZ, PZC) dominate. U types are available but less common.
• Asia: U types (Type 2, 3, 4) are very common. Z types are used for deeper projects.

My Experience
For the riverbank project (curved, moderate depth), we used U type. For the port project (straight, deep water), we used Z type. The choice depends on the project.

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What are the dimensions of gu13 sheet pile¹s?

GU 13² is a U-type sheet pile¹ designation used in some European and Asian specifications. It refers to a section with a width of 400 mm and a height of 125 mm.

GU 13² sheet pile¹ has a width of 400 mm, a height of 125 mm, a thickness of 13 mm, and a weight of 60 kg/m. The section modulus is 1,590 cm³/m. It is equivalent to U 400 x 125-13 under EN 10248 and Type 3 under the Asian Type system.

Understanding GU Series Designations

GU is a designation system used by some European manufacturers. Let me explain the naming.

GU Series Specifications

Designation	Width (mm)	Height (mm)	Thickness (mm)	Weight (kg/m)	S (cm³/m)
GU 8	400	100	8.0	40.0	900
GU 10	400	100	10.5	48.0	1,080
GU 12	400	125	10.0	50.0	1,330
GU 132	400	125	13.0	60.0	1,590
GU 14	400	125	15.0	68.0	1,800
GU 16	400	170	11.0	55.0	1,790
GU 17	400	170	13.5	65.0	2,120
GU 18	400	170	15.5	76.1	2,470
GU 20	400	170	18.0	86.0	2,800

GU 13² Detailed Specifications

Property	Value
Width	400 mm
Height	125 mm
Web thickness	13.0 mm
Flange thickness	13.0 mm
Weight per meter	60.0 kg/m
Section modulus	1,590 cm³/m
Moment of inertia	9,900 cm⁴/m
Cross-sectional area	76.4 cm²

Equivalents to GU 13²

• EN 10248: U 400 x 125-13
• Asian Type system: Type 3
• ASTM: Equivalent U section

My Experience
I have seen GU designations on projects from European-sourced materials. GU 13² is equivalent to the U 400 x 125 we used on the riverbank project. Knowing the equivalents helps when matching specifications across standards.

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What is the difference between NZ and PZ sheet piles¹?

NZ and PZ are both Z-type sheet pile designations, but they come from different manufacturers and have different interlocks.

PZ sheet piles¹ are North American Z piles with hook-and-grip interlocks, manufactured by Nucor Skyline and others. NZ sheet piles² are New Zealand Z piles with ball-and-socket interlocks, commonly used in Australia and New Zealand. The key difference is the interlock design³—PZ uses hook-and-grip, NZ uses ball-and-socket, which provides better driving performance⁴ and water tightness.

Detailed Comparison

Let me explain the differences in detail.

PZ Sheet Piles (North America)

• Interlock: Hook-and-grip
• Width: 16 inches (406 mm)
• Sections: PZ 22, PZ 27, PZ 35, PZ 40
• Typical use: General retaining, moderate depths
• Advantages: Widely available in North America, cost-effective
• Limitations: Hook-and-grip interlocks require careful alignment

NZ Sheet Piles (Australia/New Zealand)

• Interlock: Ball-and-socket (similar to Larssen)
• Width: Typically 400 mm or 600 mm
• Sections: Various, often designated by section modulus
• Typical use: Marine structures, deep excavations
• Advantages: Better driving performance⁴, improved water tightness

NZ Series Specifications (Typical)

Section	Width (mm)	Height (mm)	Weight (kg/m)	S (cm³/m)
NZ 18	400	125	60.0	1,590
NZ 25	400	170	76.1	2,470
NZ 32	600	180	81.6	3,820
NZ 45	600	210	106.2	5,730

Comparison Table

Feature	PZ Series	NZ Series
Origin	North America	Australia/New Zealand
Interlock	Hook-and-grip	Ball-and-socket
Width	16 inches (406 mm)	400 mm or 600 mm
Driving performance	Good	Excellent
Water tightness	Good with sealants	Good without sealants
Availability	North America	Australia, NZ, Pacific

Interlock Differences

• Hook-and-grip (PZ): The hook on one pile grips the grip on the next. This requires precise alignment.
• Ball-and-socket (NZ): The ball fits into the socket. This allows more tolerance during driving and tightens under pressure.

My Experience
I have supplied both types. For a project in North America, we used PZ 35. The contractor was familiar with the hook-and-grip interlock. For a project in Australia, we used NZ sections with ball-and-socket interlocks. The choice was driven by regional availability and contractor preference.

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Conclusion

Global sheet pile standards¹ vary by region. Europe uses EN 10248² with U and AZ designations. North America uses ASTM with PZ and PZC designations. Asia often uses the Type system. Understanding these standards helps you specify and order the right piles for international projects.

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