Bridging Arizona’s Freeways: How concrete bridge girders are made 

Several concrete bridge girders have been placed throughout the I-10 Broadway Curve Improvement Project and by the project’s end, dozens of these girders will have been placed within the project area. 

Bridge girders are the beams that support the deck portion of a bridge which is the part of the bridge that motorists drive on. 

Many of the concrete girders for the I-10 Broadway Curve Improvement Project are made in the south Phoenix area, off 19th Avenue and Lower Buckeye Road.

When workers begin construction of concrete girders, they first place rebar within the girder formwork which helps to enhance the structural strength of the concrete bridge girders. Tons of rebar strands can be used for just one girder depending on the height and length of the girder that’s being constructed. 

Once the rebar is in place, the form cast that shapes the concrete girder is placed around the rebar. Concrete is then poured into the girder form cast. Workers then level and smooth the surface of the concrete and let it cure or dry for two to three days.  

When curing is complete, the form cast is removed from around the concrete and the new bridge girder is revealed. Workers then conduct inspections on each girder, making sure they meet the necessary design and safety standards needed. 

View the Behind the Scenes video on concrete bridge girders below.

Learn more about the I-10 Broadway Curve Improvement Project at I10broadwaycurve.com and download the free project mobile app called The Curve.