This paper presents the implementation of a Carbon Fiber Reinforced Polymer (CFRP) composite system as a long term replacement for a non-safety, non-seismic, non-QA, low pressure service water buried pipeline. The existing pipeline (to be replaced) consists of approximately 1800 feet of large diameter (primarily 54in.), carbon steel, spiral wound, seam welded pipe, which was built and installed using AWWA standards, but is maintained in accordance with the B31.1 Power Pipe Code [1]. The CFRP pipe installation is to be done as an internal repair, and designed to comply with ASME B31.1 as a stand-alone pipe (pressure boundary). In lieu of using the limited evaluation of PCC-2 [2], which is focused on local repairs; a complete design evaluation of the entire piping system to B31.1-2010 is conducted, which is consistent with and acceptable under PCC-2. Since B31.1 does not provide detailed guidance on the design of buried piping systems, the criteria presented in this paper use the base design requirements of B31.1 adjusted to include applied soil and surcharge loads. The selected CFRP repair is the TYFO® Fiberwrap® system which consists of a carbon fiber fabric (CFRP, TYFO SCH-41-2X), and glass fiber fabric (GFRP/dielectric barrier, TYFO SHE-51A), saturated with epoxy. This composite system is built up of unidirectional CFRP layers; thus, the presented design approach also considers anisotropic material behavior, and evaluates the hoop and axial loads and capacities separately. The criteria are presented for plants considering alternative repair and replacement techniques for buried and above ground non-safety pipes.

This content is only available via PDF.
You do not currently have access to this content.