Construction methods · Piers, pylons and abutments

Cast-in-place piers with formwork lifts

The ordinary way to build a pier: steel or timber formwork panels are set on the footing, concrete is poured in lifts of 3-6 m, the panels are stripped and lifted to the next lift by crane. Cheap, flexible and slow when the pier is tall.

How bridges get built · Piers, pylons and abutments · Cast-in-place piers with formwork lifts

Also called: panel formwork, lift-by-lift pier construction, gang forms

How it is done

Cast a starter with the footing; fix the reinforcement cage for the first lift with couplers or laps for the next.
Set the formwork on the starter, plumb and brace it; pour with a pump; strip after a day and cure.
Lift the forms to the next lift; the pier head or hammerhead is formed on a shored platform or a bracket system.

Where it fits

Piers up to 15-25 m in numbers of 10-40 on a viaduct; any shape the formwork can be built for.

Where it does not

Tall piers where each crane lift costs a day; use climbing forms above about 25 m.

Plant, pace and money

PlantFormwork sets (two or three in rotation), crane, concrete pump, access scaffold.

ProductivityA lift every three to five days per set; a 15 m pier in two to three weeks.

CostUSD 400-700 per m3 of pier concrete in place.

Risks and controls

What goes wrong

Formwork blowouts, cold joints, cover loss at lift joints, falls from height.

Quality assurance

Plumbness surveyed every lift, cover meter checks, cube tests, joint preparation between lifts.

Examples

The default pier construction in the game's schedule for piers under 15 m.