A Study for the Practicality of the 3D Full Model in the SSI Analysis on the Nuclear Power Plant

This study is a part of research project ‘the practicality of the 3-D Full Model in the SSI (Soil-Structure Interaction) Analysis on the Nuclear Power Plant’ from June 2006 to May 2009. The purpose of the project is getting advanced and more accurate results with the practicality of Full Model SSI analysis. The SSI analyses of the NPP were being performed for the APR1400 (Advanced Power Reactor 1400MWe) design because the APR1400 was developed as a Standard NPP concept enveloping suitable soil conditions. The soil properties of SSI analyses were from lower bound characteristics to firm condition. The Standard NPP that was developed in early 1990 had the rigid foundation assumption because rigid mat had many advantages, simple modeling and quick calculation. But this assumption may create licensing issue because the rigid mat could include uncertainties in the modeling and analysis procedure. Now, the advanced computing capacities can offer the calculating environment using Full Model in the SSI analysis, and through this study the Full Model SSI analysis may be applied to the NI (Nuclear Island) of APR1400. The full modeling concept can be distinguished into two methods. First one is the Full Model about excavated soil part below the ground surface only, the super structures can be beam sticks. Another modeling is the Full Model about excavated soil part below ground surface together with the super structure. Finally, the Full Model of excavated soil part with the super structure was built, each structure of the Full Model was verified.