Abstract: Rebar for reinforcing a concrete includes a core, a rib layer, and a cover layer. The rib layer is placed over at least a portion of the core and the cover layer is placed over at least a portion of the rib layer. A method for making the rebar for reinforcing a concrete includes providing a core, placing a rib layer over at least a portion of the core, and placing a cover layer over at least a portion of the rib layer.

Abstract: A single spring unit includes a multi-helical spring formed of composite material. The single spring unit includes multiple layers of composite material disposed in a first helical configuration, and multiple layers of composite material in a second helical configuration interwoven with one another, and coupled together to form the single spring unit.

Abstract: A single spring unit includes a multi-helical spring formed of composite material. The single spring unit includes a multiple layers of composite material disposed in a first helical configuration, and multiple layers of composite material in a second helical configuration interwoven with one another, and coupled together to form the single spring unit.

Abstract: The invention presents a non-metallic laminated composite reinforcing rod for use in reinforced or prestressed concrete. The rod is made by creating a sheet of core material comprising a number of layers of "pre-preg" material. Ribs are formed on top of the core from additional layers of pre-preg material laid with the fibers transverse to those in the core. The ribs are then covered by additional layers of pre-preg laid with fibers parallel to the core fibers. The material is heated to fuse the layers. Finally, the sheets of laminated reinforcement are cut parallel to the core fibers to the width desired. The resulting reinforcing rod is superior to steel in corrosion resistance, flexibility, durability, and strength. The reinforcing rod may be used as a prestressing tendon in prestressed concrete after encasing the ends of the rod in an attachment formed of a sleeve filled with groutingmaterial such as mortar or epoxy. The glass-fiber embodiment is non-conductive.