Patent ID: 8083203

Claim:
A recyclable formwork for forming an upright concrete structure, said formwork comprising: a plurality of retaining devices, each device comprising: an elongated support; a first and second pair of spaced-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, each channel being adapted to receive an edge of a panel therein in a snugly relationship; and a plurality of panels arranged successively one relative to the other between two successive retaining devices, each panel being fitted into the corresponding channels of the adjacent retaining devices so as to provide an inside forming cavity between the panels adapted to receive concrete therein; a tubular envelope mountable around the panels forming the cavity; and a plurality of reinforcing paperboard sheets stacked between an inner side of the tubular envelope and outer sides of the panels to provide an enhanced mechanical rigidity to the formwork; the retaining devices, the panels, the tubular envelope and the reinforcing elements being made of a recyclable material.