设计基准内压下混凝土安全壳的有效预应力作用研究

Study on Effective Prestressing Effects on Concrete Containment Under the Design-basis Pressure Condition

核电厂安全壳建造过程中大量采用预应力技术,预应力在设计基准内压下的分布状况、损失规律直接影响到安全壳结构的耐久性。介绍了某核电厂安全壳结构和预应力系统的布置情况和预应力损失的分析过程,以闸门洞口附近水平预应力钢束为例进行了预应力损失计算,同时计算了5年打压试验时安全壳结构的有效预应力。基于以上分析,利用ANSYS程序建立预应力混凝土安全壳有限元模型进行结构计算,对设计基准内压下的有效预应力作用进行了总结。结果表明,预应力系统承担了打压试验下大部分设计内压,安全壳整体结构是安全的,这些结论与安全壳的预应力系统设计理念一致,可供工程设计人员参考。

Prestressing technology is widely used in nuclear power plant containment building, and the durability of containment structure is affected directly by the distribution and loss of prestressing value un- der design-basis pressure. Containment structure and the distribution of prestresseing system are introduced briefly. Furthermore, the calculating process of horizontal prestressing bunch loss near the equipment hatch hole is put forward in details, and the containment structure prestressing loss when 5-year pressure test is obtained. Based above analysis, the finite element model of the prestessed concrete containment structure is built by using ANSYS code, the prestressing effect on concrete containment is analysed. The results show that most of the design pressure is beared by the prestressing system under the design-basis pressure, so the containment structure is safe. These conclusions are consistent with prestressing containment system design concepts, which can provide reference to the engineering staff.