The UPRR (Union Pacific Railroad) was the owner of this project. This design-bid-build project required an 8150’ flyover structure to be built to alleviate the bottleneck created by the intersection of UPRR and BNSF (Burlington Northern & Santa Fe) Railway tracks in the area. Minimal interruption to the track, the proximity to the 10 freeway, a small construction footprint area, and soft soils found in the area, required an innovative construction to solve these issues and increase the feasibility of this complex project.

Cellular concrete offered the exact solution to this project, but this was the first time it had been used in this quantity or height. The material eliminated the need for conventional RW structures but also assisted with the overburden pressure on soft soils and reduced the impact on design in an area known for its high seismic activity due to the low density of this backfill material. Two mobile batch plants were able to produce over 2,000 CY of material each day and placed a total of 220,000 CY—the largest placement since 2007. No reported/observed performance issues or concerns have been observed to date.