500m口径球面射电望远镜馈源支撑结构体系试验研究与理论分析

为将来在中国建造世界上最大的射电望远镜(简称FAST),采用了索、塔及移动小车馈源支撑结构体系。本文对此结构体系进行了1/30缩尺模型试验研究和理论分析,获得了模型结构索中张力和结构动力特性沿馈源球冠的变化规律。理论分析结果和试验结果二者吻合较好,说明本文的分析方法和分析过程是可行的,具有较高的计算精度。分析结果还表明,在进行结构动力反应分析中,小车的扭转振动不容忽视。

Experimental Study and Theoretical Analysis of the Structure for Supporting the Feed Cabin of the FAST

A structural system is presented with its behavior studied in this paper. It consists mainly of cables, towers and a moving car for supporting the feed cabin of a five hundred meter spherical telescope(FAST). FAST will be built in China to become the largest radio telescope all over the world. The experiment of a 1/30 scale model has been carried out. From the experiment the distribution regularity of the cable tension forces and the natural frequencies of the structure are obtained where the moving car is located at the scope of the feed trace. Based on the finite element package named ANSYS, a nonlinear FEM is used to analyze the static and dynamic characteristics of the structure. The theoretic results are in good agreement with those of the experiment. The results obtained show that the proposed analysis technique and procedure can be used to predict correctly the structural behavior, and that the torsional vibration of the moving car should be emphasized in structural dynamic response analysis.