Glass Reinforced PlasticAny of a variety of thermoplastic and thermoset material used in sewer construction (e.g., high-density polyethylene, polypropylene, PVC, fiberglass reinforced plastics, polyester felt reinforced pipe, epoxy and polyester mortars, etc)., a family of rehabilitation linings. Often generically known as Reinforced Plastic Mortar (RPMReinforced Plastic Mortar; a form of thermoset plastic pipe.) and Reinforced Thermosetting Resin (RTRReinforced Thermosetting Resin; a form of thermoset plastic pipe within the GRP family.).
