City of Columbus Pipeline
While attempting to install telecommunications lines below a creek, a driller punctured a buried, 48 in. dia. prestressed concrete cylinder pipe (PCCP). The pipe is part of Columbus’s water system that supplies water to more than one million people in the area. The punctured pipe was below the creek bank and adjacent to a bridge making it difficult to access for external repairs. SGH assessed the damage and designed internal carbon fiber-reinforced polymer (CFRP) repairs.
The pipeline runs parallel to a state roadway and slopes down at 60 to cross below the nearby creek. Due to environmental issues associated with the creek, difficult access to the puncture location along the steep embankment (pictured upper right), presence of a 47 cu yd concrete thrust block at the top of the embankment, nearby location of various utilities, and proximity to the bridge abutment, it was difficult to excavate the pipe for evaluation or repairs.
After the damaged pipeline was removed from service, SGH entered the pipeline to assess the damage and document existing conditions. We worked with the contractor to develop means and methods for redirecting the creek water flowing into the pipe through the puncture (pictured middle right), to restore the internal surface of the pipe, and to design a standalone CFRP liner capable of resisting all design loads, including a maximum pressure of 250 psi, without relying on the host pipe.
SGH collaborated with the contractor throughout the work, including stemming initial infiltration from the creek and monitoring installation of the CFRP liner. During construction, we inspected pipe surface and material preparation, observed the liner installation, and performed laboratory tests to determine the liner’s degree of cure prior to putting the pipeline back in service.