Concrete Strengthening Improvements with FRP
This post takes a look at two projects that show the power of fiber-reinforced polymer (FRP) for concrete strengthening and tank repair projects. The projects come from two very different sectors: One was undertaken by a municipality to head off problems with its aqueduct system, while the other was executed for the benefit of a natural gas plant’s construction team. Still, both serve as valuable examples of FRP’s uses.
1998–2000: The Providence Problem and Solution
The first project dates back to 1998. That year, the Providence Water Supply Board—the municipal entity overseeing the water supply of Providence, Rhode Island—encountered a major issue: A water line in Cranston, Rhode Island, had encountered a major failure. The line, which was 102″ in diameter, was essentially a concrete cylinder, and it failed because of “corroded prestressing wires,” according to Jay Thomas and Robert St. John of Water & Wastes Digest.
This ruptured pipe was particularly alarming because it called into question the structural soundness of the rest of the aqueduct, parts of which had been installed as many as 50 years earlier. Concerns about the system were valid: An inspection showed that 20 sections “within a five-mile stretch of the pipeline” had vulnerabilities. Each section was 16 feet in length, so the problem was indeed widespread.
To carry out the repairs, the Providence Water Supply Board eventually selected the contractor SPS. The contractor identified FRP tank repairs as a cost-effective way to repair the pipes. Despite beginning repairs in January 2000—during a New England winter—SPS successfully used FRP sheets, coatings, and other materials to make the repairs and stay on budget. The project ended up serving “as a model” for other water utilities, per Thomas and St. John, speaking to its success.
Late 2014: A Challenging Construction Project
In Colorado late in 2014, the project developers in charge of building a natural gas plant had a problem. Some 56 days after construction began, the “the concrete in 20 circular columns” was underperforming, per Ben DuBose of Materials Performance. The plans called for a design strength rated at 4,000 PSI, yet the concrete was achieving only half that. This created a “lower margin of safety.”
The project’s engineer was aware of FRP products from Milliken Infrastructure Solutions (MIS). That company came on board and worked through the issues with the construction project planners.
Eventually, both parties came to the conclusion that three layers of FRP wraps would be an attractive solution. MIS supplied these for the struggling columns, and the wraps ended up enhancing their strength until it was very close to the target of 4,000. As was the case with the Providence project, the Colorado project crew dealt with challenging winter weather, but they planned ahead and used tenting and pumped-in heat to allow work to continue. The project was overall successful—another echo of FRP’s victory in the Providence project, some 14 years earlier.
Picon FRP, Inc. Full Service Tank Repair and FRP Concrete Strengthening
Picon is a full-service repair provider for industrial fiber reinforced plastic (FRP or fiberglass) and tank linings, tank coatings, tank repairs, and industrial sand blasting. Contact us today or call 510-232-0065 to discuss your project needs.