Bridging by Segmental Box Girder

Bridging by Segmental Box Girder

SEGMENTAL BOX GIRDERS SYSTEM
Introduction.
Segmental box girders (segments) system is used for building superstructure for bridges / other structure in replacement of conventional construction via pre-cast beams and cast-in-situ decks. Segments will be pre-cast at another location preferably at outskirts of city. New setup of casting shall be done specifically to carry out the segments casting works. Segments are cast using specific moulds as the shape and dimension are also specific. Moulds may be made out of cut and weld steel sections and other accessories to complete the moulds. The cast segments later shall be brought to site and erected at specific location via launching girder system (or other method) by continue joining segments to each other to form the completed decks in between of two piers. Post tensioning in form of stressed groups of strand wires shall keep the segments together and provide the strength required to support the required loading on the deck. Further works can then be carried out as per requirement prior opening to users.

Advantages of using segmental box girders system (comparing to conventional method)
The segments system reduces the environmental disturbance compare to the conventional method by carrying out the concreting works further away from the construction site where is usually located at city centers.
Quality can be maintained since the casting of segments shall be carried out at control environment as compared to carry out at site.
Aesthetic of using segments system is better due specific shape can be cast if so required by clients.
Since segmental box girders are pre-cast elements, casting of segments can proceeds while piling works, pile-caps, piers, pier caps construction are proceedings at site. Therefore, shorter duration of construction is achievable.