Patent ID: 8206060

Claim:
A sheet element for reinforcing, separating and draining large structures, comprising a sheet body which has a lattice configuration with main wires and transverse wires that are stretched respectively along two mutually substantially perpendicular directions and that intersect in nodes, said main wires extending in an extrusion direction of a blank that provides said sheet body, said main wires having an upper rim and a pair of substantially vertical lateral walls extending downwardly from said upper rim at opposite ends of said upper rim, an upper pair of mutually opposed edges being arranged at said opposite ends of said upper rim where said upper rim intersects with said lateral walls, said main wires having a lower rim in regions remote from said nodes, said lateral walls intersecting said lower rim at opposite ends of said lower rim, a lower pair of mutually opposed edges being arranged at said opposite ends of said lower rim where said lower rim intersects with said lateral walls, said main wires having a lower portion in regions at said nodes which converge with said transverse wires, said main wires having at the regions at said nodes a thickness, in a direction that lies at right angles to a plane of arrangement of said sheet body, which is equal to at least three times a thickness of said transverse wires, and said main wires having at the regions remote from said nodes a thickness which is at least two times greater than the thickness of said transverse wires.