Pile wall

[edit] Introduction

Piles are long, slender, columnar elements that can be driven into the ground to provide stability, such as in foundations. They are typically made from steel or reinforced concrete, or sometimes timber.

Pile walls can be used to create permanent or temporary retaining walls. They are formed by placing piles directly adjacent to one another.

[edit] Types of pile walls

There are several types of pile walls, including:

[edit] Contiguous pile wall

These are closely spaced pile walls which are defined in Groynes in coastal engineering (CIRIA C793), published by CIRIA in 2020 as ‘…cast-in-place concrete piles immediately adjacent to or touching each other. Sometimes used for plank piles.’

If there are gaps between the contiguous piles, these can be sealed with a substance that creates a watertight retaining wall. Contiguous pile walls are sometimes used for the construction of cellars or basements. This allows the piles to be installed and then used as a retaining wall during the excavation process.

For more information, see pile foundations.

[edit] Secant pile wall

These are interlocking pile walls, which, depending on the composition of the secondary intermediate piles, can be hard/soft, hard/firm or hard/hard secant walls. Secant pile walls are formed by constructing reinforced concrete piles that interlock, and are often used as a cost-effective solution when short-term water retention is required. Secant piles are reinforced with either steel rebar or steel beams.

For more information, see secant pile wall.

[edit] Tangent pile wall

This type of pile wall is not as commonly used as contiguous pile walls. They are like secant pile walls except the piles are constructed flush to each other, so there is no pile overlap.

[edit] Sheet pile wall

There are also pile walls that are made from sections of sheet materials with interlocking edges that are driven into the ground to provide earth retention and excavation support. Sheet piles are most commonly made of steel, but can also be formed of timber or reinforced concrete. These are commonly used for retaining walls, land reclamation, underground structures such as car parks and basements, in marine locations for riverbank protection, seawalls, cofferdams, and so on.

For more information, see sheet piles.

[edit] Soldier pile and lagging wall

Soldier pile and lagging walls are used as a form of embedded excavation support that uses vertical beams (or soldiers) and horizontal lagging placed at regular intervals. These are then grouted to keep the soil out of the excavation. The soldier piles are often made from steel while the lagging is typically made of timber or precast concrete. This technique is sometimes used for temporary excavations or foundation pits.

[edit] Related articles on Designing Buildings

• Basement excavation.
• Coastal defences.
• Flood defences.
• Pile foundation.
• Piling equipment.
• Retaining walls.
• Secant pile wall.
• Sheet piles.
• Types of excavation.