Abstract
This paper deals with a hyperbolic paraboloidal four mass system which is considered to be the simplest network of hanging roofs. Consisting of hanging, pretensioning and bracing cables, the present system is analyzed by the small deflection theory. Investigation is made of the characteristics of the deflections, the natural frequencies and the corresponding modes. The following results are obtained from this study. 1) In case of doubly threaded nets, the prestressing takes much effect on the natural frequency of the antisymmetric mode defined in this paper. 2) In case of quardruply threaded nets, the bracing members put restrictions on the oscillation of the above mentioned mode. On the natural frequency, the prestressing is not so effective but these bracing members give remarkable effects. On the basis of this study, some suggestions are made for the practical design of hanging roofs.
