PIPELINE REHABILITATION, TYFO® SYSTEM
OVERVIEW
Fibrwrap Construction was selected to perform the rehabilitation work. The scope of work included strengthening nine (10) segments of PCCP, including conducting the required surface preparation, end detailing, fiber installation, finish coat installation and all the required quality control measures. Both the return and supply cooling water lines had segments which required structural strengthening. The access limitations only allowed for man entry and ventilation on each end of a the two 1,200-ft long segments of pipe.
The general installation procedure for the CFRP system went as follows:
1. Prepared the exposed concrete substrate to concrete surface profile.
2. Before the CFRP system is installed, prepared three 2 ft. x 2 ft. mockup areas in the pipeline with one layer of the CFRP system using the same surface preparation and installation methods to be used for the repair pipes per ASTM D4541.
3. Removed mortar lining at joint ends, at least 18 inches to thevsteel can, for proper termination of the CFRP system.
4. Installed CFRP layers in the hoop and longitudinal directions as required by the AWWA C305 design requirements.
5. Placed the hoop layers of the CFRP system in narrow widths as needed to conform to sloped surface in joint recess. Staggered the seams of the narrow hoop layers in subsequent layers.
6. During the repair of pipes, prepared at least one 2 ft. x 2 ft. witness panel (test panels) per day per work shift on a level surface using one layer of the CFRP system and the same material and techniques used for the fiber wrap installation in the above listed pipes.
7. After the installed CFRP system has become tack free, inspected all surfaces for voids, delaminations, wrinkles and raised fabric edges, and perform corrective actions.
8. Cured the CFRP system using curing schedule approved by the engineer. Pipeline can be refilled after the CFRP system completes at least 85% cure based on Barcol or Shore D hardness.
9. Final inspection and acceptance of work. The project was completed on time and below budget and the customer was very pleased with Fibrwrap’s confined space safety program. LCRA was very complimentary of Fibrwrap’s performance in supplying, designing and installing the specified Fyfe® Tyfo® product within the aggressive outage schedule.
PROJECT DETAILS
Project: LCRA – Fayette Power Station, Unit 3 – CW Pipe Rehab
Location: LaGrange, Texas
Pipe Length: 160-ft
Pipe Size: 48 inch and 120-inch PCCP
Installation Method: CFRP wet lay-up
Owner: Lower Colorado River Authority
Engineer: Fyfe Co. LLC
Contractor: Fibrwrap Construction
“This being the first time LCRA utilized CFRP materials, our team didn’t know what to expect. Fibrwrap Construction showed up at the site and were very professional with their equipment setup, especially their confined space plan implementation and equipment setup. After auditing several safety tailgate meetings at the beginning of the project, our management team was very impressed by the company’s safety culture and relaxed the rest of the project. LCRA appreciates the professionalism of Fibrwrap’s entire team…... from management, all the way through your crews.”.
JD Killien, Project Engineer
LCRA