Construction methods · Finishing, articulation and maintenance

Bearing replacement

Bearings wear out or corrode long before the bridge does. The deck is jacked a few millimetres at the pier, the old bearing removed, the plinth repaired and the new bearing set; often under traffic with lane closures.

How bridges get built · Finishing, articulation and maintenance · Bearing replacement

Also called: bearing renewal, jack-and-replace

How it is done

Survey the deck and pier; design jacking points and check the deck for the jacked condition; provide traffic management or restrictions.
Jack the deck in synchronised steps with locks; cut out the old bearing, repair or rebuild the plinth, install the new bearing with grout.
Lower onto the new bearing, verify contact, record.

Where it fits

Any bridge with accessible bearings; the reason the game rewards bearing types that can be replaced.

Where it does not

Bridges with no jacking space or inaccessible bearings, where the pier head must be modified first.

Plant, pace and money

PlantJacks and synchronised control, brackets, grouting kit.

ProductivityA pier in a few days.

CostUSD 30,000-300,000 per pier depending on access and traffic.

Risks and controls

What goes wrong

Cracking the deck by differential jacking, traffic loading during jacking, unknown deck condition.

Quality assurance

Jacking plan, load logs, bearing contact check.

Examples

Routine on 30-50 year old viaducts; rocker bearings are the usual victims.