Patent 11873613 was granted and assigned to Hubbell Incorporated on January, 2024 by the United States Patent and Trademark Office.
Disclosed is a cover for a utility vault and a method for making such covers. The cover is formed from fiberglass reinforcement layers, a low-density core, and a polymer mix matrix. The reinforcement layers include a bottom reinforcement layer, one or more edge reinforcement layers, and a top reinforcement layer. A first portion of the edge reinforcement layer overlaps a portion of the bottom reinforcement layer and a second portion of the edge reinforcement layer overlaps a portion of the top reinforcement layer. The core is positioned between the top and bottom reinforcement layers. The reinforcement layers are formed from fiberglass fabric and may include fiberglass layers whose fibers are oriented quadraxially. The polymer mix impregnates the fabric layers, encases the core, and binds the components together. The polymer matrix includes a thermoset polymer resin.