Difference between pipe pile and sheet pile?

Steel piles, as an important material for support and foundation structures, mainly include two types: pipe piles and sheet piles. Steel piles play a crucial role in bridge, construction, port, foundation pit and coastal engineering.

Bridges and high-rise buildings: Steel piles provide a solid foundation for supporting super-large structures by being driven into deep and relatively hard strata.
Port and river engineering: It is used for the construction of docks, retaining walls, embankments, sea walls, hydraulic revetments, etc., effectively preventing soil erosion.
Foundation pit support and temporary enclosures: During the excavation of deep foundation pits, they are used to maintain soil stability and enhance construction safety.
Due to its fast construction speed, strong load-bearing capacity and wide adaptability, it has become an indispensable basic material in modern engineering.

Pipe pile
Steel pipe piles are cylindrical steel pipes that can be made by seamless, welded or spiral welded methods. Their size range is very wide, with common sizes ranging from 8 inches to over 50 inches. It is an efficient load-bearing component that can meet different load-bearing requirements.
Steel pipe piles are usually driven into the ground by hammering, vibration or drilling. They can be driven in with an open or closed end. When the closed end is used, concrete can be poured to enhance the overall compressive strength and uplift resistance of the steel pipe piles.

Performance advantages:
It has excellent vertical load support capacity and is suitable for bearing heavy structures, such as Bridges and building foundations.
After injecting concrete, combined piles can be formed, significantly improving the bending and shear resistance performance.
During the pile driving process, frictional compaction of the surrounding soil can effectively enhance the lateral frictional resistance.
It can achieve splicing to extend the pile length, and the on-site construction is flexible and convenient.

In addition, in hydraulic structures, steel pipe piles can also be used as "main piles", combined with sheet piles to form composite walls, which are used in structures such as water retention and bank protection.

Sheet pile
Steel sheet piles are flat steel plates with interlocking grooves at their edges. They form continuous walls by interlocking with each other and are driven underground by pile drivers. Common shapes include U-shaped, Z-shaped, flat plate and other cross-sectional shapes, providing different bending and shear resistance properties.

Main uses:
Retaining soil and water structures (wharf retaining walls, sea dikes, riverbanks);
Foundation pit support and cofferdam (cofferdam)
Environmental isolation barriers, garage underground walls, etc.
It is used for land return projects and temporary construction support, and is convenient for dismantling and reuse.

Features: It forms a continuous closed wall with good sealing performance. Quick to install and recyclable, suitable for both temporary and permanent applications.

The main differences between steel pipe piles and steel sheet piles are as follows:

1. Cross-sectional structure
Steel pipe piles are cylindrical steel pipes that can be filled with concrete and can have either closed or open ends. In contrast, steel sheet piles are long and strip-shaped structures, mainly in shapes such as U-shaped and Z-shaped, with lock grooves along the edges, capable of forming continuous walls.
2. Main Functions
Steel pipe piles are mainly used to support vertical loads and deep foundation bearing, and are suitable for heavy structures. Steel sheet piles are mainly installed as part of retaining structures and are used for slope protection and foundation pit protection. Suitable for foundation pits and temporary support, etc.
3. Bending resistance
Pipe piles can be filled with concrete. After filling, the combined piles have stronger bending resistance and better performance. The bending resistance performance of sheet piles is relatively low, and they mainly bear the pressure of water and soil rather than structural loads.
4. Installation method
Pipe piles can be installed by striking and driving in or by drilling and then pouring, and their lateral friction resistance can jointly compact the soil layer with concrete. Steel sheet piles usually interlock with the lock grooves at the edges to form a closed wall structure, but their side friction resistance consolidation effect is not as good as that of pipe piles.
5. Flexibility
Steel pipe piles can be spliced and extended, and their dimensions are easy to adjust. Steel sheet piles are all modularly designed, with their lengths limited by standard profiles and relying on interlocking installation.
6. Recycling and reuse
Pipe piles are not often recycled. After being buried, they can be used permanently. Sheet piles can be recycled and reused, making them suitable for temporary engineering applications.

Summary

Steel pipe piles are widely used in heavy-duty foundation engineering due to their excellent vertical bearing capacity, concrete filling combination capacity and side friction compaction effect of deep foundation pits. Steel sheet piles, on the other hand, construct continuous retaining walls through interlocking structures, which are suitable for retaining soil, water and temporary construction support. In engineering design, the type of pile to be used should be selected based on specific geological conditions, load types and structural requirements, and even combined for application to give full play to complementary advantages.