Pieresearch® has long been a leading manufacturer and distributor of centralizer products for reinforcing cage alignment and support in geo-construction. In 2019 the company received a U.S. Patent (U.S. Patent No., 10,151,113) for their UNIBAR® Centralizer, a revolutionary alignment device to be used in the installation of tiebacks, soil nails, micropiles, augercast piles and other earth retention and deep foundation support elements that employ a single bar or tendon. These include Single Bar, Multi-bar/Strand Anchors, Encapsulated (DCP) Anchors, and Steel or Plastic Pipe Applications. The newest addition to the UNIBAR® line is the adjustable Quick-Lock® UNIBAR®. It has an adjustable hub that accommodates rebar sizes from #6 through #11. The adjustable UNIBAR® is designed to keep the reinforcing tendon/bar centered in an 8" diameter bore hole.
Pieresearch’s UNIBAR® system addresses some of the main concerns facing geo-constructors and geotechnical & structural engineers, those being quality control and quality assurance. Engineers seek the confidence that the deep foundations and support systems they design are built as intended. Geo-constructors strive to deliver a reliable product. Proper grout and concrete placement is a key ingredient in successful construction. In order to achieve proper design strength in any drilled and grouted borehole, the tendon or rebar anchor must be centered in the hole to allow the required grout or concrete cover throughout its critical length. Without proper alignment the rebar or tendon cannot perform the function for which it was designed, and may become compromised over time due to corrosion and/or misalignment. In that the support element is encased in grout or concrete as part of the installation process, it cannot be inspected after the grout or concrete is placed in the hole. The employment of the UNIBAR® Centralizer directly addresses these concerns.
UNIBAR® Centralizers are made of durable, non-corrosive plastic consisting of two identical halves that are fast and easy to snap together. They accommodate a wide range of rebar and tendon sizes. As an example, Pieresearch® offers UNIBAR® Centralizers with a 4" O.D. to fit rebar sizes ranging from #5 up to #20. To facilitate the installation process Pieresearch® provides easy to follow assembly and placement guidelines. UNIBAR® Centralizers are lightweight, easy to assemble and can be attached with zip ties or tie wire. No nuts or bolts are required for installation. UNIBAR® Centralizers are designed to fit between rebar threads and very importantly, they are economical.
Field tested and field proven, the UNIBAR® Centralizer has been used on jobs throughout North America. Recent projects include the new stadium for the Texas Rangers Baseball Team, multiple highway jobs for the Texas Department of Transportation as well as for the North Texas Transit Authority, highway projects for the Oklahoma DOT, the University of Arkansas parking garage, the Fort Leavenworth Transient Barracks, and many more.