该文介绍了500 m口径球面射电望远镜（five-hundred-meter aperture spherical radio telescope，FAST）反射面单元的组成和工作原理。对三角形单元的滑动故障和结构损伤原因进行了力学建模与分析，提出了免于故障和损伤的改进建议，包括3种自适应连接机构的新型布局、反射面单元故障判断方法和自适应连接机构设计改进等。该文力学模型可以帮助望远镜维护人员分析三角形反射面单元故障和损伤的主要原因，预测故障发生模式和可能发生故障的危险单元分布位置，从而有针对性地进行改进。该文有助于望远镜维护人员在日常巡检中通过目测手段，及时发现反射面单元的异常现象，防止问题继续恶化，有利于未来设备维护和更换。
This paper describes the configuration and operating principle of the five-hundred-meter aperture spherical radio telescope (FAST) reflector elements with sliding failures and the resulting structural damage analyzed using mechanical modelling of the triangular reflector elements. Design improvements were then developed to avoid such failures and damages, including new arrangements of the adaptive connecting mechanisms, element failure identification methods and upgrade of the adaptive connecting mechanisms. The analysis model helps maintenance staff find the main reasons for triangular element failures and predict possible failure modes and damaged element positions to develop improved designs. The results enable the staff to more quickly locate abnormal reflector elements using routine visual inspection and prevent the worse failures to improve equipment maintenance and enable future upgrades.
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