  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.
