Precast segmental erection methods

The prefabricated segments are transported by truck or barge to the erection site. They are then installed symmetrically on either side of the supports using gantry cranes or floating cranes, mobile handling equipment fixed to the deck and launching girders. This construction method is adapted to long structures (deck span from 30m to 60m) with multiple spans; it combines the advantages of cantilever construction together with segment prefabrication.

Following installation and commissioning, our lifting frames can operate independently, providing both lifting and self-launching mechanisms. While the gantry crane is used for medium and large projects, this method is suitable for smaller, long span structures (30m to 170m). It is particularly versatile and applies both to precast segmental decks and cable-stayed decks (either precast, composite, or steel) regardless of span range and segment weight. The equipment can be reused for other projects.

This method consists of assembling a complete span as it moves forward. The span is made of segments that are hung on a launching gantry and are assembled by pre-stressing while the span is placed on the piers.

The technique is applicable to prestressed concrete bridges, continuous spans, multiple spans not exceeding 50m, and spans with steeply curved alignment, regardless of the longitudinal and plane profiles of the structure.

The method is based on the use of launching beams, beam launchers or lifting frames capable of receiving prefabricated beams (I-, U- or T-beams) behind, below or parallel to the erection system. Strand and winch lifting systems are used, ensuring precise placement of the precast elements, with several degrees of alignment possible and at an efficient rate.