Cable nets represent the ultimate in elegant minimalist structural systems, and provide optimum transparency when the effect of a sheer glass membrane is desired. Frei Otto developed and popularized cable nets as a structural system in the 1960s and 70s. But it was architect Helmut Jahn and engineering firm Schlaich Bergermann that applied the technology in a most innovative manner for the Kempinski Hotel in 1992. The Munich hotel’s flat cable net supported glass facade fueled worldwide interest in cable nets as astructural form in glass facade applications.
This structural system supports glass by a net geometry of pre-tensioned cables. Designs can be flat, or the net can be pulled into double curvature. A clamping component locks the cables together at their vertices and fixes glass to the net. The net structure’s large prestress loads require early coordination of the facade contractor with the building engineer.
Cable nets are remarkably minimal structures when the boundary steel required to accommodate typically high prestress loads is ignored. Cables and fixings are often specified as stainless steel, resulting in highly durable, low maintenance glass walls, as seen at One North Wacker in Chicago, Illinois.
Cable prestress must be applied in the field via complex hydraulic jacking processes. Installation means and methods are a primary consideration for all cable structures.
This enormous cable net utilizes bridge cables and spans approximately 300 feet.
Double-curved cable nets are also achievable. The Security & Exchange Commission Headquarters building in Washington, D.C. includes a 60’x90’ double curved cable-net wall and 60’x60’ skylight.