Nonmetallic duct bank with nonmetallic subducts

A duct bank for enclosing utility lines underground, the duct bank comprising:

• a first main duct formed from a nonmetallic material and defining an interior volume therewithin, the first main duct having a circular cross-sectional shape;
• and
• a plurality of sub-ducts each formed from a nonmetallic material and being disposed in the interior volume of the first main duct;
• each of the plurality of sub-ducts having a circular cross-sectional shape and being configured to carry one or more utility lines,
• wherein the nonmetallic material of the first main duct includes one or more of:
• glass reinforced polyester (GRP), a hybrid fiber-reinforced epoxy-based laminate, or glass-reinforced vinyl ester,
• wherein the nonmetallic material of each of the plurality of sub-ducts includes one or more of:
• GRP, high-density polyethylene (HDPE), or polyvinyl chloride (PVC);
• a second main duct formed from the nonmetallic material of the first main duct and defining a second interior volume therewithin, the second main duct having a second circular cross-sectional shape;
• the first and second main ducts each having an axial end;
• and
• a coupler that interconnects the axial end of the first main duct and the axial end of the second main duct, wherein the coupler is formed from GRP,
• wherein the coupler comprises a pair of elastomer or rubber bands that are embedded or mounted at an interior surface of the coupler and extend about a full circumference of the interior surface of the coupler.