54/Plumbing Engineer October 2021
and I really liked the flexibility of PP-RCT to handle it. PP-RCT is an awesome product - the flow characteris- tics of the pipe, its light weight and flexibility, and the ease of lifting and maneuvering it - all these benefits are huge compared with steel. In fact, we're already using it on other projects." The radiant loops also were designed with the move- ment of the bridge in mind. "We designed to match the way they wanted to pour the bridge, so the PEX loops would never cross an expansion joint," he explains. "Each loop connects to its own custom-built manifold in the slab of that section of the bridge, which then connects to the PP-RCT pipe. REHAU supplied custom coil lengths to minimize the number of circuits and optimize the snow- melting design." The design used 34,500 feet of 5/8 inch RAUPEX O
barrier PEX tubing for the snowmelting loops embedded in the concrete pathway, which is supplied with heated antifreeze through 1,900 feet of 2 1/2-inch to 4-inch (75 mm to 125 mm) PP-RCT supply-and-return pipe. The 5/8-inch PEX tubing was fastened directly to the bridge deck rebar at 6-inch on-center spacing before being encased within concrete. The tubing was connected to fabricated manifolds installed within the bridge deck and accessible via access panels. Each manifold is sup- plied with a heated antifreeze solution by the PP-RCT pipes. "The UVU Bridge project is an excellent example of how polymer piping materials such as PEX and PP-RCT can meet demanding project needs that metals can't pro- vide," states Lance MacNevin, P. Eng., director of engi- neering for PPI's BCD. "The polymer piping materials were able to provide benefits for not only the installer - in relation to faster, easier and safer installations - but also to the structure itself - regarding weight, flexibility and corrosion resistance." He adds: "The bridge is a showcase to professionals in the commercial construction industry that polymer pipe is the future of smarter building design, capable of meeting project and installer demands while providing long-last- ing service and performance. Upon completion, the UVU Bridge project became the largest installation of a hybrid PP-RCT and PEX snow/ice melting system so far." Frailey notes: "This bridge is a very effective applica- tion of a hydronic snow/ice melting system. I can't imag- ine any other practical way of removing the snow, and it operates very cost-effectively as well." O Steve Cooper has reported on a variety of plumb- ing, construction and infrastructure projects for several decades. Based in New York, he has traveled extensively to conduct on-site news interviews with professional engi- neers, contractors, government officials and representa- tives of major companies supplying the industry. Cooper can be reached at 516-623-7615 or steve@scacommuni- cations.com.
The new pedestrian bridge at Utah Valley University required more than six miles of 5/8-inch REHAU RAUPEX O
barrier PEX tubing for the snowmelting loops embedded in the concrete pathway. Photo: REHAU The Uponor PP-RCT supply-and-return pipe system provides heated antifreeze for the snowmelting loops of the new bridge. Photo: Uponor