Construction methods · Heavy lift, moving and accelerated construction

Prefabricated bridge elements and systems (PBES)

The systems view of accelerated bridge construction: footings, columns, caps, girders with deck attached, full-depth deck panels and even complete spans as prefabricated modules with engineered connections, assembled on site in days. The game's precast pier and full-span options are parts of this.

How bridges get built · Heavy lift, moving and accelerated construction · Prefabricated bridge elements and systems (PBES)

Also called: PBES, prefabricated bridge units, modular bridge elements

How it is done

  1. Standardise elements and connections: grouted couplers, UHPC joints, post-tensioned connections.
  2. Fabricate off site in parallel with foundations; deliver in sequence.
  3. Assemble with cranes or SPMTs during short closures; use UHPC or rapid-set grout for connections that reach strength in hours.

Where it fits

  • Bridge replacements on busy routes, repetitive viaducts, sites with weather windows, seismic regions with tested connections.

Where it does not

  • One-off geometries, sites without fabrication capacity, projects where connection performance is unproven.

Plant, pace and money

PlantPrecast plant, transport, cranes, grouting and UHPC mixing.
ProductivityDays on site per span.
CostHigher element cost, lower site cost and user delay.

Risks and controls

What goes wrong

  • Connection quality, tolerance stacking, transport damage.

Quality assurance

Connection mock-ups, grout and UHPC tests, geometry checks at delivery.

Examples

US FHWA Every Day Counts programme; Korean and Japanese modular overpasses.

Related methods

Further reading

FHWA Connection Details for PBES · AASHTO LRFD Guide Specifications for ABC