Arch structures, unlike beams, are purely compressive and must be attached to the ground at each end to resist outward thrusts. Arches are near-ideal structures in that the form closely follows the force lines of the structure.
This arch is a portion of a circle.
The body of the structure is a circular group of 12 thin rods which are held in position by bulkheads. It has a "roadway" contained within the rod group and 24 lamps.
The rods are 1/8" stainless steel with threaded ends.
Rod Array Arch
Design and Fabrication: Carl Pisaturo, 2005.
Stainless Steel Rods, Polycarbonate Bulkheads, Aluminum End Bulkheads and Butresses, Light Bulbs. Length 80"
Constructing curved things from straight elements requires some help. To achieve something close to the designed form required a series of cradles mounted to a surveyed and marked plywood surface. To these cradles the 13 bulkheads were clamped, and then the rods were laced through the bulkheads. Once the rods were in place, set screws were tightened to lock the form. The arch could then be removed and would keep its shape.