Octa's transportation blog

Construction Technique Saves Time on I-405 Bridge

As part of the I-405 Improvement Project, crews are building, widening and replacing 18 bridges.

Because no two bridges are alike, each requires careful assessment and planning. At the Bolsa Chica Road bridge, for example, the length of the span -- the distance between two intermediate supports – helped determine a time-saving construction approach by using concrete box girders to rebuild the new bridge instead of using wooden falsework.

On only a few of the project’s bridges, concrete box girders are used to form the support structure. Because the span of the Bolsa Chica Road bridge is shorter, crews were able to use precast girders brought to the site for placement. 

This bridge is being rebuilt in two stages – one half at a time – which allows it to remain open to traffic during construction. Once the first half of the bridge is rebuilt, traffic will be switched onto it, and the second half will be demolished and rebuilt. The bridge will be widened to eight lanes from four. 

Learn more about the I-405 Improvement Project here.