Adjustable Radius Formwork System | Radius Circular Formwork
Construction of an Oxidation Ditch, Clarifier, and Aerobic Digester using Formwork
The city of Nicholasville, Kentucky, awarded Cincinnati, Ohio contractor Dugan and Meyers LLC with the expansion project at the Jessamine Creek Environmental Control Facility. Located in Nicholasville, the wastewater treatment plant currently treats 4.3 million gallons of wastewater daily; the expansion will increase that amount by 73 percent.
With a cost of $20 million, the project’s focus is to increase the capacity to treat water before returning it to the environment. The increased capacity will be accomplished by constructing an additional clarifier tank, an anerobic digester tank, and an oxidation ditch.
Dugan and Meyers chose EFCO as their formwork supplier of choice to provide the lowest in-place concrete cost solution for the expansion of the Jessamine facility.
Circular Formwork is Easily Adjustable
When collaborating with EFCO on a formwork solution for this construction project, Dugan and Meyers emphasized the need for a formwork system that could easily adjust to the four different radii needed to form the oxidation ditch and the clarifier tank. Additionally, they requested a formwork solution to shape all the straight walls on the oxidation ditch and digester tank. Following the construction plan, the crew started building the oxidation ditch first.
Cast-In-Place formwork used for Oxidation Ditch
EFCO engineered a cast-in-place formwork solution for the oxidation ditch that included approximately 2600 ft2 of leased EFCO REDI-RADIUS® formwork and 2200 ft2 of EFCO LITE® wall formwork. The equipment was shipped directly from the closest EFCO warehouse in Columbus, Ohio. EFCO’s solution also included detailed assembly and cycling methods that enabled the Dugan and Meyers crew to assemble 16’ tall x 54’ long gangs. These large gangs equated to one and a half sets of forms; one set to place concrete in and one half to tie rebar against for the next pour.
Oxidation Ditch uses Radial Concrete Walls
The design of the oxidation ditch includes four radial concrete walls at each end, all with different radii. The Dugan and Meyer crew cast the innermost radius using a 180-degree EFCO Round Column form and a job-built form to act as the inside form. The EFCO REDI-RADIUS system can adjust to any radius 18′ or larger and was used to form the three outer walls. For their formwork cycling method, they cast one radial wall and moved the formwork setup to the opposite end to shape the same-sized radius wall.
How to Shape Radial Formwork | Circular Formwork
On the jobsite, the Dugan and Meyers construction crew quickly adjusted the formwork to the radius required for each section of the oxidation ditch and the clarifier tank by using EFCO’s shaping table. Constructed of EFCO SUPER STUDS® and lumber cut to the desired radius, the table can increase productivity by shaping both the convex and concave panels.
Meeting Expectations with Minimal Formwork
The Dugan and Meyers crew made approximately 62 concrete pours to complete the three structures; 54 of that total was for the oxidation ditch alone. EFCO’s all-steel concrete formwork solution met their expectations with a simple solution that included a minimum amount of formwork that is easy to use, safe and reliable.
EFCO Formwork Specialist-Columbus
Ric Klinedinst, Senior Territory Manager
Dan Burns, District Engineer
Brian Jenne, Field Supervisor
Dugan and Meyers LLC
Addison Weatlley, Project Manager
Tim Twiddy, Project Superintendent