Fit-in GFRP Liner for Retrofitting Corroded Metal Culverts

Corrugated metal pipes (CMPs) have been used as culverts in North America since the 1950s. Today, corrosion of CMPs is a major problem that requires an urgent and efficient solution to retrofit thousands of corroded CMPs across the country. One potential solution gaining wide acceptance is to use a fit-in Glass Fiber Reinforced Polymer (GFRP) liner inside the old CMPs and to connect them using polymer grout. In this paper, a methodology to retrofit corrugated metal culvert using a fit-in GFRP profile liner was developed and implemented. First, material characterization of the GFRP material and the epoxy grout were carried out for proper design of the retrofit system. Second, full-scale CMP-GFRP composite section was tested under three-point bending configuration to observe the retrofitted culvert behavior to failure. The new CMP-GFRP section develops full composite action and shows failure capacity of 75 kip with a deflection of 3.52 in at the end of the test. Post failure of the polymeric grout, GFRP pipe failure was observed at mid-span location starting on the tension side. A finite element model was developed to understand the behavior of the CMP-GFRP composite pipe and to allow for the efficient design of the proposed retrofitting system.