Which method involves driving piles along both sides of an existing wall and inserting a needle in the form of pile caps through the existing one?

Pile method is useful in clayey soils and for waterlogged areas and for walls carrying heavy loads. For underpinning very light structures, the piles are driven along the structure and then brackets or cantilever needles are provided to carry the structure.

Additional Information Classification based on Method of Installation

Screw piles:

• These piles are screwed into the soil by means of hydraulic jack

Driven piles:

• Timber, steel, or precast concrete piles may be driven into position either vertically or at an inclination.
• If they are inclined then they are called as "Batter" or "Raking" piles. Pile hammers and pile-driving equipment are used for driving piles.

Bored and Cast-in-situ piles:

• Only concrete piles can be cast-in-situ.
• As the Holes are drilled and filled with concrete.
• These are straight-bored piles or 'under-reamed with one or more bulbs at intervals Reinforcements is used according to the requirements.

Driven and cast-in-situ piles:

• A closed end casing or a shell is driven into the ground. Later casing is filled with concrete. eg. Franki piles.

Jack piles:

• These are piles driven into soil by means of a hydraulic jack.