Construction methods · Driven piles

Timber piles

The oldest pile: a tree trunk driven tip-first, usually treated against decay. Light, cheap, and adequate for small bridges and temporary trestles in soft ground where loads are modest and the piles stay below the water table.

How bridges get built · Driven piles · Timber piles

Also called: treated timber piling, wood piles

How it is done

Select straight, seasoned logs 250-400 mm at the butt; treat with preservative.
Drive with a light hammer and a driving ring to protect the head; avoid overdriving.
Cut off below the permanent water level or protect the head with a cap.

Where it fits

Temporary trestles and falsework, small rural bridges, historic replacements, soft ground with 100-400 kN per pile.

Where it does not

Any exposure above the water table without treatment; marine borers; hard driving.

Plant, pace and money

PlantLight crawler rig or crane-hung hammer.

Productivity15-30 piles per shift.

CostUSD 30-80 per metre.

Risks and controls

What goes wrong

Brooming of the head, decay at the water line, borer attack in the sea.

Quality assurance

Straightness and treatment certificates, driving records.

Examples

Temporary trestles for river bridges worldwide; Venetian foundations are the famous permanent case.