Applicability of genetic algorithms (GAs) to the form optimization problem of structures is discussed in this paper. The form optimization problems on truss structures under the prescribed displacement mode are solved by using GAs. These problems have strong nonlinearity, and the layout of the members is deeply concerned with the existence condition of solutions. In the present study, the form finding method in which not only the positions of the objective nodes but also the layout of the members are encoded to strings in the GAs as the design parameters of the structure is proposed, and the effectiveness of the method is examined. Moreover, the form finding method is extended to the minimal surface problem, in which several control points of a spline function are introduced in order to sescribe the shape of the membrane surface.
