Next, WVU worked with the USACE to design GFRP wicket gates measuring 16 feet long, 4 feet wide and 8 inches thick. The composite design is corrosion-resistant and provides equal or better mechanical properties than a wooden wicket gate. It’s also compatible with the original hardware, which makes it easier to replace and operate the gate. Composite Advantage in Dayton, Ohio, fabricated the gates using vacuum-assisted resin transfer molding (VARTM). The gates underwent various bending tests at WVU, then the engineers made some design modifications. For example, they added an ultra-high molecular weight polyethylene layer on the face of the wicket gates to help prevent abrasion and ice damage.
The gates, installed last August on the Illinois River, are working well so far. They will be pulled from the river and inspected this summer. Equally important to their performance is the anticipated cost savings for the two locations on the Illinois River using wooden wicket gates. “Because of the extended lifetime of the composite gate versus a wooden gate, as all of the wooden wicket gates are changed over, we calculate a savings of almost $19 million over a 50-year lifetime,” says Lampo. “We’re hoping that will kick start interest in the use of composites for other more demanding lock and gate structures.”
With approximately 87,000 dams listed in the National Inventory of Dams, which is maintained and published by the USACE in conjunction with the Association of State Dam Safety Officials, there certainly is a lot of potential for FRP materials. The floodgates are open for composite solutions.