At the downtown Chicago Social Security Ad‑ ministration building, a new playground with low, curving concrete walls was designed as part of the Harold Washington Center. When PerDel Construction received the subcontract from F.H. Paschen Construction for this project, Per Del called on Symons® by Dayton Superior to help them create a plan for the pours.
There were several important considerations for this project. There were a variety of curves in the design, and the contractor was con‑ cerned about wasting a lot of time building templates and making formwork adjustments between pours. The plans also specified a smooth architectural finish without “chord‑ ing”, and they did not want to spend a lot of time grinding and finishing the surface to meet this requirement.

Symons proposed using the Flex‑Form forming system for this project. By simply bolting on different sets of factory-rolled ribs between pours, the curves could be accurately produced with a minimum of labor. This steel-faced sys‑ tem also produces smooth concrete surfaces that greatly reduces time-consuming finishing operations common with other systems.

When PerDel accepted the proposal, Symons engineers produced plans and drawings for building the walls in eight pours. The plans utilized standard ribs wherever possible, and custom rib configurations, including the tight “return wall”, only where needed. This saved the contractor money, since they were able to rent almost all of the equipment necessary to complete the project.

PerDel Construction was impressed with the detailed plans and the equipment they re‑ ceived. They reported that the project went smoothly, and the walls looked terrific.

Flex-Form® System