背架结构是FAST(500m口径球面射电望远镜)反射面支承结构的重要组成部分,其性能直接影响到FAST的工作精度、经济性乃至项目的可行性.针对2008年我国南方地区发生严重雪灾的实际情况,对单层、单层弦支、双层、局部双层四种形式的FAST背架结构重新进行了参数优化,最后从结构自重、刚度、施工难易程度等方面对四种结构形式进行了综合性能的比较.
Back-structure is an important part of FAST(Five-hundred-meter Aperture Spherical Telescope),whose performance affects the whole telescope's working-precision、economical performance and the project's feasibility.In 2008 winter,a disastrous snowy weather took place in south China,and the location place of FAST also suffered the unexpected snow.Taking the case into account,optimization for back-structure was conducted again taking the disastrous snow-load into account.Four kinds of structuretypes are involved in the optimization.Finally the general-performance of the four kinds of structure-types are compared from three aspects—weight,rigidity and complexity.