核电厂负刚度阻尼隔震结构的地震响应研究

隔震技术能有效减小核电厂上部结构的加速度响应，但强地震作用下隔震层位移过大会导致管道断裂。本文基于曲面运动原理及预压弹簧伸缩特性提出了一种负刚度阻尼系统，通过球铰在拱球面曲线运动实现负刚度特性，并在弹簧压缩方向提供黏滞阻尼性能。提出了负刚度系统的理论恢复力模型并进行了力学特性分析，设计了负刚度装置并完成了静力试验，结果显示理论恢复力模型与试验结果的一致性较理想。将核电厂负刚度阻尼隔震结构与核电厂隔震结构进行了地震响应对比分析，比较了不同地震波输入下的地震响应。结果表明负刚度阻尼系统可有效同时减小核电厂上部加速度响应和隔震层位移响应。

Seismic Response Analysis of Isolated Nuclear Power Plant Based on Negative Stiffness Damping

Isolation technology can effectively reduce the acceleration of the superstructure of the nuclear power plant (NPP), however, under the strong earthquake, the large displacement of the isolation layer may lead to pipeline breakage. In this paper, a negative stiffness damping (NSD) system was proposed based on the principle of surface motion and the prestressing spring expansion and contraction. The negative stiffness was achieved by the spherical hinge movement on the curved surface of the arch, and its viscous damping worked in the spring compression direction. The theoretical restoring force model of negative stiffness system was also put forward and its mechanical properties were analyzed. The negative stiffness device was designed and the static test was competed. The test results are highly consistent with the theoretical restoring force model. The comparative analysis of seismic responses between isolated structure with NSD nuclear power plant and that with isolated nuclear power plant was carried out. By comparing the seismic responses under different seismic wave inputs, the results show that the proposed NSD system can effectively reduce the upper acceleration response and isolation displacement response.