System solutions study on the fatigue of the fast cable-net structure caused by form-changing operation

The Five-hundred-meter Aperture Spherical Radio Telescope (FAST) is supported by a cable-net structure, whose change in form leads to a stress range of approximately 500MPa. This stress range is more than twice the standard authorized value. The cable-net structure is thus the most critical and fragile part of the FAST reflector system. In this study, we first search for a more appropriate deformation strategy that reduces the stress amplitude generated by the form-changing operation. Second, we roughly estimate the tracking trajectory of the telescope during its service life, and conduct an extensive numerical investigation to assess the fatigue resistance requirements. Finally, we develop a new type of steel cable system that meets that cable requirements for FAST construction.