Patent ID: 8313080

Claim:
A recyclable formwork for forming a polygonal upright concrete column, said formwork comprising: a plurality of retaining devices, each one of said plurality of retaining devices comprising: an elongated support; and a first and a second pair of space-apart substantially parallel walls extending along the elongated support and projecting outwardly therefrom for providing first and second holding channels extending angularly to each other; a plurality of rigid wood-based flat-shaped panels arranged successively one relative to the other between two successive retaining devices of the plurality of retaining devices, an edge of each panel being snugly fitted into the corresponding channel of the successive retaining devices so as to provide an inside forming cavity between the panels adapted to receive concrete therein, wherein each of said panels is provided with an inner impervious plastic sheet liner; and a plurality of straps surrounding said cavity when the panels are forming the cavity, wherein overlapping ends of said plurality of straps are securely gripped to one another, and further wherein the straps being in direct contact with the retaining devices and the panels for hooping the panels and allowing the panels to be retained therein when mechanical stress is exerted on the panels by concrete being poured in the cavity.