BigPatents India

A three-dimensional constructional element (10) is shown having opposing and substantially planar panels (30, 40) mounted on opposing surfaces of a flexible planar member in the form of a flexible mesh material layer (52) therefore making a composite sheet of three layers. Panel (30) includes transverse grooves (12, 14) formed therein and panel (40) includes transverse grooves (16, 18) formed therein. The structure is deformable about each groove (12, 14, 16, 18). In a preferred embodiment the panels (30, 40) are divided into many segments defined by the transverse grooves to allow the constructional element to be deformed so that one of the exterior surfaces of panel (30) is concave while the opposing exterior surface of panel (40) is convex. Also disclosed herein is a method of forming a curved surface structure including the steps of deforming the constructional element (10) into a desired position and securing the element (10) into that position by introducing a grouting material (74, 94) thereon to so that the grouting material can enter the grooves (12, 14, 16, 18) to rigidly affix the element (10). (FIG.1 )