Experimental and numerical study on the seismic response reduction effect of TMD on nuclear cabinets using shaking table test

Improving the seismic performance of equipment is required for safety of nuclear power plants (NPPs). In particular, electric cabinets are installed in multiple places of NPP and include electronic devices inside. Thus, damage to the cabinet under earthquakes can adversely affect the NPP safety and operation. This study conducts a real-scale shaking table test and experimentally confirms the seismic response reduction effect of a tuned mass damper (TMD) on the NPP cabinet. Specifically, the shaking table test identifies the cabinet dynamic characteristics first. Then, the TMD device is designed and manufactured, and the seismic and dynamic responses according to the presence of the TMD are compared and analyzed through the real-scale shaking table test. Also, the effect of such a TMD is experimentally investigated even when the cabinet dynamic characteristic is changed. Finally, a numerical model is derived based on these test results. As a result, it is confirmed via the test that the TMD decreases seismic responses of the cabinet by about 14-31%. Also, such a TMD decreases seismic responses of the cabinet by 14-25% even if the target cabinet dynamic characteristic is modified. Finally, the numerical models are well created and validated for further investigation on multiple cases.