A new ramp along I-29 in Sioux City, Iowa, required an 85 ft. bridge to span over an aging conduit carrying Perry Creek. Precast Bulb T-Beams were set just above the existing conduit, resulting in low headroom between the two structures. Cramer & Associates sought to use stay-in-place forms to speed placement of the deck and avoid the tedious task of constructing and removing temporary wood deck formwork.




Historically, Iowa DOT has not allowed the use of stay-in-place forms due to the inability to inspect the concrete deck through the form (corrugated metal or precast concrete). Constructing plywood forms and tearing them down within a tight space would be difficult, labor intensive, and likely impact the construction schedule.


Cramer & Associates partnered with TrueTech Bridge to design and supply ClearCast Forms to speed construction, reduce labor, and meet the requirement for visibility. The Iowa DOT approved of ClearCast Forms because of the transparency, allowing their inspectors to see the condition of the concrete over the service life of the deck. Because ClearCast Forms are customized to fit each project, Cramer & Associates was able to quickly install the lightweight ClearCast Forms with their own crew of two laborers, without heavy equipment or specialized labor. Cramer & Associates was pleased to move onto other tasks upon completion of the deck pour, and the Iowa DOT was impressed with the function and clarity provided by the forms.