URETEK Thrives on its “Can Do” Attitude
If a structural or geotechnical challenge seems insurmountable, URETEK would like to take a look at it. If there are no other alternatives, URETEK wants to see how it can help. Occasionally, a project comes along that requires ultimate attention to detail and the combination of many solutions that come not only from URETEK processes, but its people as well. Such as the case for Ameristar, currently the largest ornamental fencing company in the world. Located in Oklahoma, this facility boasts of a high-volume, state-of-the-art rollforming, metal processing, powder coating equipment. The equipment used to move the steel coils of fencing across the manufacturing line require precise balance and an extremely strong concrete foundation to supply the turnstile with the proper footing to complete such a heavy task. A small shift or tilt from a turnstile could be disastrous for the company. URETEK ICR Oklahoma received a call from one of the company’s engineers stating that one of the turnstiles was “listing” to the south when rotated looking like the “Leaning Tower of Pisa.” Each turnstile has four arms to hold each coil, when three coils are unloaded the remaining coil’s weight caused the turnstile to shift (about -1/2”) due to unstable soil at the base of the turnstile.
About the Client
Each steel coil weighs 50,000lbs. along with the concrete foundation measured at 30 inches thick under the turnstile puts a live load on the soil to be around 250,000lbs. Due to the heavy nature of the project, URETEK ICR Oklahoma consulted with various engineers and specialist of URETEK USA (Roads & Highways) along with URETEK ICR (Industrial, Commercial) divisions to form a solution. URETEK Roads & Highways division, has over a decade of experience using expanding polymers to lift extremely heavy loads (Related article: “Leaning Tower of Milk”). URETEK USA also specializes in airport runway stabilization where 30+ inches of concrete is common.
After a thorough evaluation a specialized repair plan was developed using both The URETEK Method® (injection of high density structural grade polymer directly below the base or footing of the settled concrete to lift or stabilize concrete) and URETEK’s Deep Injection® Process (injection of high density expanding polymers at depth to solidify and compact the soil to increase the load bearing capacity under heavy structures).
As part of the execution phase of the repair, ICR Oklahoma diagramed the base of the turnstile in a clock face manner. This layout allowed the operations to accurately lift the most distressed portion of the foundation first. While drilling 1/2” injection holes under the turnstile, the crew confirmed the foundation to be approximately 30” thick. URETEK’s Deep Injection® Process was used while the turnstile was in the “dead load” or unloaded condition. The Deep Injection process raised the turnstile +.6 inches. The turnstile was then put in the “live load” or loaded condition with a 50,000 pound coil of steel on each arm bringing the total weight to approximately 250,000 lbs. URETEK’s Deep Injection Process was used again in the planned manner resulting in another +.6 inches of lift. After a set of injections was made, operations then used The URETEK Method™ in a grid pattern on 4 foot centers surrounding the base of the Turnstile to stabilize and fill any remaining voids. The turnstile was then rotated several times with one arm loaded trying to simulate the original failure. The turnstile remained stable and level during all rotations. The total amount of lift was recorded at +1.2 inches.
Completed in 6 hours (after hours) the restoration of the turnstile resulted in no down time for Ameristar’s production line.