江门中微子实验中心探测器主体不锈钢结构设计研究

Design and research of the main stainless steel structure of the central detector of Jiangmen Underground Neutrino Observatory

江门中微子实验（JUNO）中心探测器主体不锈钢结构工程属于国家重大科技基础设施建设项目。首先根据工程的设计要求,以降低有机玻璃的应力水平为主要目标,在前期研讨成果基础上进一步确定主体结构体系为单层不锈钢网壳＋590个不锈钢撑杆＋有机玻璃球＋底部支承结构。针对本工程的重点和难点,逐一对结构的稳定性、结构关键构件的内力分布、地下地震动参数分布规律、流固耦合效应、关键节点的应力状态、施工过程对结构的影响等方面展开深入的研究,完成一系列的有限元分析及力学试验研究工作。有限元分析及力学试验结果表明,通过对不锈钢撑杆的内力分布和幅值的优化设计,有机玻璃的应力水平得到了有效控制,运行工况下最大主拉应力不大于4MPa;考虑非线性及初始缺陷的结构整体稳定性系数为3.45。主体不锈钢结构具有良好的承载力和稳定性,满足设计要求。

Jiangmen Underground Neutrino Observatory（JUNO） central detector main stainless steel structure project is a major national science and technology infrastructure construction project. Firstly, according to the design requirements of this project, based on the results of the previous research, the main structural system was further determined to be a single-layer stainless steel mesh shell ＋ 590 stainless steel struts＋ acrylic balls＋bottom support structure with the aim of reducing the stress level of acrylic. In view of the key points and difficulties of the project, the stability of the structure, the internal force distribution of the key components of the structure, the distribution law of the ground motion parameters, the fluid-solid coupling effect, the stress state of the key nodes, and the influence of the construction process on the structure were conducted in-depth research, a series of finite element analysis and mechanical test research work were completed. The results of finite element analysis and mechanical tests show that the stress level of acrylic is effectively controlled by the optimization of internal force distribution and amplitude of stainless steel struts. The maximum tensile stress under operating conditions is not more than 4 MPa. The overall structural stability coefficient of the structure considering nonlinear and initial defects is 3.45. The main stainless steel structure has good bearing capacity and stability to meet the design requirements.