A Study of Influences of Value Variations of Structural Parameters on Forces in Cables in the Net Structure of Cables of the FAST

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is supported by a net of cables, which enables the FAST antenna surface to be a real-time paraboloid through active control. The FAST project is now entering the stage of construction and implementation. However, considerable errors exist in practice and can result in deformation of the net from its ideal shape. In order to maintain structural safety of the FAST it is necessary to perform certain sensitivity analysis of the net for value deviations of structural parameters. In this paper we reasonably consider the variation ranges of structural parameters. We then perform certain analysis of the sensitivities of the net structure to value deviations of single parameters and to simultaneous value deviations of multiple parameters. Specifically, we use a finite-element model to investigate influences of value variations of structural parameters on the static forces in the net. We conclude that value variations of several key parameters such as the cable blanking length and cable elastic modulus have large impact on the forces in cables. Our results for simultaneous value variations of multiple parameters indicate that the variation range of forces in cables of the net is -19% to 27%.