SHAPES OF MAXIMUM RIGIDITY FOR TENSION STRUCTURES

Abstract

A geometrically unstable structure constituted by bar-members, such as a tensegrity or a cable net, which is stabilized by prestressing, is usually very deformable, especially when it is subject to asymmetrical loading. In view of the above, the authors have developed a nonlinear programming method with nonlinear domain equations to find its minimum deformation shape. The present paper gives a method, which adopts general reduced gradient method (GRG) with linear domain equations, to find the optimum shape with maximum rigidity of a tension structure. By this method, the analysis procedures can be simplified and the computer calculation can be speeded up. The present paper demonstrates that the shape of maximum rigidity of a tension structure is dependent on the loading patterns, but not on the module of the load vector. A tensegrity frame is taken as an example for the numerical analysis.