Fabrication and erection of steel and concrete girders involve distinct processes, with steel requiring cutting, shaping, welding, and surface treatment, while concrete girders are typically cast in segments or full spans. Both require careful planning and execution, including surface preparation, structural assembly, and quality control.

Steel Girder Fabrication and Erection:

Fabrication:

This involves cutting, shaping, welding, and assembling steel components like plates and sections. It includes processes like flame cutting, cold sawing, punching, and drilling.

Surface Treatment::

Steel girders undergo surface preparation like cleaning and coating (painting or metal coatings) to protect against corrosion.

Quality Control:

Throughout fabrication and erection, quality is maintained through visual inspections, non-destructive testing (like dye-penetrant testing), and adherence to approved Welding Procedure Specifications (WPSS).

Concrete Girder Fabrication and Erection:

Casting:

Concrete girders can be cast in segments or as full spans in a casting yard or at the bridge site.

Prestressing:

Prestressed concrete (PSC) girders utilize prestressing strands to enhance strength and durability.

Erection:

Full-span girders may be transported to the site and launched using specialized systems. Segmental girders are erected piece by piece, with each segment joined to the previously erected ones.

Joints:

Site welding may be required for connecting members, requiring careful alignment and secure positioning.

Quality Control:

Concrete mix design, curing processes, and the integrity of joints are critical aspects of quality control in concrete girder construction.