A structural reinforcement device for providing support to a roof and/or walls of tunnels, mines and/or shafts, the device comprising a frame having a longitudinal axis, at least a portion of the said longitudinal axis being generally arcuate, the frame comprising at least three laterally spaced longitudinal rods (104, 106, 108) arranged generally parallel with each other and with the longitudinal axis of the frame, the longitudinal rods being linked together by one or more laterally extending linking member, the or each linking member being arranged to link the longitudinal rods together in an undulating manner to thereby form an upper plane in which at least a first of the longitudinal rods is situated (104, 108) and a lower plane in which at least a second of the longitudinal rods is situated, the frame further comprises securing means operable to allow the frame to be secured to an adjacent surface, wherein the securing means comprises the second of the longitudinal rods and which is an undulating longitudinal rod attached to a securing longitudinal rod, wherein the undulation may cause the undulating longitudinal rod to deviate away from and back toward the securing longitudinal rod, thereby forming a plurality of apertures, the frame being obtainable by the following process: applying a first pressure to at least three longitudinal rods on a grid of overlapping rods, the longitudinal rods being parallel with a longitudinal axis of the grid, to thereby deflect the longitudinal rods to which the first pressure is applied from the plane of the sheet; applying a second pressure to a portion of the at least three longitudinal rods to which the first pressure is applied at one or more position between lateral rods to thereby cause the at least three longitudinal rods to which the first pressure is applied to buckle and form an arcuate portion on a longitudinal axis; and adding a further longitudinal rod to a portion of the at least three longitudinal rods to which the second pressure has been applied to thereby secure the rods in their buckled position and reinforce the arcuate portion of the longitudinal axis of the frame. the frame further comprises securing means operable to allow the frame to be secured to an adjacent surface, wherein the securing means comprises the second of the longitudinal rods and which is an undulating longitudinal rod attached to a securing longitudinal rod, wherein the undulation may cause the undulating longitudinal rod to deviate away from and back toward the securing longitudinal rod, thereby forming a plurality of apertures, applying a first pressure to at least three longitudinal rods on a grid of overlapping rods, the longitudinal rods being parallel with a longitudinal axis of the grid, to thereby deflect the longitudinal rods to which the first pressure is applied from the plane of the sheet; applying a second pressure to a portion of the at least three longitudinal rods to which the first pressure is applied at one or more position between lateral rods to thereby cause the at least three longitudinal rods to which the first pressure is applied to buckle and form an arcuate portion on a longitudinal axis; and adding a further longitudinal rod to a portion of the at least three longitudinal rods to which the second pressure has been applied to thereby secure the rods in their buckled position and reinforce the arcuate portion of the longitudinal axis of the frame.