Commuters heavily rely on the popular Union Pacific / North Line, a Metra line running through the Chicago metropolitan area. Metra recently commissioned the reconstruction of this line due to the overall age and associated strenuous use. This reconstruction included a retaining wall by Elevate Infrastructure from Fullerton Avenue to Webster Avenue with the purpose of building up and supporting future railway.
The original engineering plans specified this wall as cast-in-place. Upon learning about Elevate's precast alternative, the general contractor, Kenny/Granite Construction, proposed the precast option to better align with the project's accelerated schedule. According to Bill Moore of Kenny/Granite, “Once we learned the Elevate wall system did not require special backfill, we could easily see its advantage.”
Elevate's innovative, patent-pending, precast counterfort system was designed to support the future embankment using backfill onsite. The system includes a precast concrete base and a precast concrete face with integral counterforts. Low strength material is pumped under the base to ensure proper bearing on the foundation soils while high strength grout is utilized at the joints between the base and face with integral counterfort. This grout mechanically fastens the sections together along with the use of cast-in bar anchors. The overall ease of installation surpassed the expectations of both the general contractor and owner.
Elevate offers various sized pieces depending on a project's criteria. The pieces used for this project were 12'-11” wide and 15'-0” to 18'-4” in height. Special consideration was given to pieces in close proximity to the existing buildings along Fullerton Avenue, where space was limited. Kenny asked if Elevate could provide lighter weight units due to the restricted access. Since our units are easily customizable, we were able to accommodate, by providing smaller width, lighter units. Bill Moore explained, “It was very easy to work with Elevate's engineering team to customize the wall during the original design as well as during installation when unique situations occurred due to the nature of this site in a highly established urban environment.” |