U-shaped steel sheet piles
Structural features: The cross-sectional shape of U-shaped sheet piles is "U", with the lock openings located at the edges. They can form continuous walls through interlocking. It has a relatively large lateral stiffness and better bending resistance than linear piles, making it suitable for small and medium-sized foundation pits, wharf revetments and other scenarios.
Performance advantages: It has excellent strength and rigidity, and can effectively resist bending moments and shear forces. For the convenience of construction, U-shaped steel sheet piles are relatively stable during the driving construction process and have better torsional resistance than some other types. It has good symmetry, and the force is evenly distributed after installation, making it convenient to form a continuous pile wall.
Construction advantages: It can be driven by vibrating hammer or static pressure method, with low noise and high speed, and is suitable for soft soil areas.
Limitations: The material utilization rate is relatively low, and the strength of the cross-section is relatively less economical than that of the Z-type. The width is relatively narrow, and the forming efficiency of the wall is not as fast as that of the Z-shaped one. It is limited in large-depth scenarios and is not suitable for ultra-deep foundation pits or deep-water retaining walls.
Typical application scenarios
Temporary enclosure: Road widening, foundation pit support (such as subway construction).
Waterborne works: quay walls, flood control embankments (requiring coordination with water-stop measures).
Z-shaped steel sheet piles
Structural features: The cross-section of Z-shaped sheet piles presents a "Z" shape, with the lock openings symmetrically distributed on both sides of the neutral axis. The continuous web design can effectively increase the section modulus and moment of inertia. It has a higher bending strength and can withstand greater lateral pressure. During construction, it needs to be used in conjunction with internal braces, and the construction complexity is relatively high.
Performance advantages: It has a high section modulus. Under the same weight conditions, its bending resistance is superior to that of U-shaped ones. It has strong integrity. After multiple pieces are spliced together, the force is more uniform and it can withstand greater pressure. The construction efficiency is high, the width of each piece is large, the setting speed is fast, and the number of lock openings is reduced.
Construction advantages: It has a relatively large cross-sectional width, which can reduce the number of splices and increase construction efficiency. The lock is tight and has better water-stopping performance.
Typical application scenarios
Cofferdams in deep soft soil areas: such as foundation pits for comprehensive pipe galleries and large-scale river course improvement.
Corrosion resistance requirements: Anti-seepage walls in coastal areas or chemical industrial parks.
Comparison: U Type vs Z Type Steel Sheet Pile
| Feature | U Type Sheet Pile | Z Type Sheet Pile |
| Section Shape | U-shaped | Z-shaped |
| Single Pile Width | Relatively narrow (400–500mm) | Wide (600–700mm or more) |
| Bending Resistance | Moderate | High |
| Stiffness | High stiffness per single pile | Strong overall stiffness after combination |
| Construction Efficiency | Average | Fast, fewer piles needed |
| Typical Applications | Temporary excavations, quay walls, cofferdams | Deep excavations, permanent structures, large port projects |
| Cost-effectiveness | Moderate | Excellent (high material utilization) |
| Reusability | Good, easy to extract | Poor, difficult to extract |
Common misunderstandings about sheet piles
1. The performance of all types of sheet piles is approximately the same
Many people think that as long as it is a sheet pile, it can be used universally. In fact, U-shaped, Z-shaped, straight-web shaped and I-shaped types vary greatly in terms of section modulus, strength, ease of construction and reusability. If the selection is made blindly, it may lead to structural overconfiguration or insufficient strength.
2. Steel sheet piles are all disposable materials
In fact, U-shaped and some straight-web type sheet piles can be pulled out and reused multiple times, making them particularly suitable for temporary projects. Misunderstandings can lead to overestimation of procurement costs and increase unnecessary budgets.
3. The greater the thickness, the better the performance will definitely be
Although increasing thickness can enhance strength, the design of cross-sectional shape is often more important than simply thickening. For instance, under the same weight conditions, Z-shaped often has better bending resistance than U-shaped.
Read more : What is steel sheet piling