Patent ID: 7591108

Claim:
A double-curved load-bearing prefabricated shell, the shell comprising: a plurality of triangular sherds, wherein each triangular sherd is formed as one part of a bisection of an ordinary quadrilateral section of a surface defining longitudinal and transverse directions, the ordinary quadrilateral section having four section sides and four corner points and a net of first and second arrays of curves intersecting at node points of a C 1 -continuous surface so as to define a plurality of planar quadrangular meshes between chords of the first and second arrays of curves, with an equal number of quadrangular meshes being defined in both the longitudinal and transverse directions, at least respective chords of the first array of curves being parallel to one another, wherein a cutting curve connecting two diagonally opposing corner points and intersecting a plurality of node points bisects the ordinary quadrilateral section so as to form the triangular sherd bounded on one side by the cutting curve connecting two cut corners of the ordinary quadrilateral section and on two sides by array sides being two remained ones of the four section sides, the two array sides meeting at an array corner and each connecting to one cut corner of the sherd, wherein the cutting curve intersects a plurality of node points so as to bisect a plurality of meshes such that the triangular sherd includes a plurality of the unbisected quadrilateral meshes and a plurality of cut triangular meshes; wherein two sherds are fused into a double sherd having a continuous surface transition at the respective identical cutting curves, which form a cut-seam curve such that respective node points of each of the respective cut triangular meshes are connected and that each of the cut triangular meshes are fused into a quadrangular seam mesh having four coplanar node points and two sets of non-parallel opposing chords; and wherein at least six of the plurality of sherds are disposed so as to meet at one point shared by one of their respective both cut corners so as to form a surface whose node points define a C 1 -continuous surface.