Session: SE-07-01 Seismic Evaluation of Systems, Structures and Components

Paper Number: 107126

107126 - Study on Analysis Procedure Using Integrated Three-Dimensional Fe Model for Reactor Coolant System by Applying to Shaking Table Tests for Scaled Mock-Ups 

Generally, seismic stress evaluation for a Class 1 component of a nuclear power plant is performed using Finite Element stress analysis with seismic loads that are obtained another calculation.
In Japan, a multimass beam model is usually employed to calculate seismic loads for components in a reactor coolant system (RCS) of PWR plant. The components are modeled into simple elements such as mass points and beams in the multimass beam model.
So far, three-dimensional FE analysis (3D-FEA) has been applied to stress analysis for each portion in a component. Recent advances in computer performance, however, have made large-scale analysis possible, and 3D-FEA for not only whole of a component but also the integrated all components in a RCS is not difficult at the present time.
If the integrated whole 3D-FE model of RCS is employed, stress due to seismic can be directly calculated by applying seismic waves to the 3D-FE model, and the multimass beam model is not necessary. 
So, we are developing a stress evaluation method that uses an integrated 3D-FE model consisted of all components in RCS, which is called “Seamless Structural Analysis Process”.
As a validation for this method, this method has been applied to the shaking table tests for scaled mock-ups previously conducted by the Japanese national projects and the results are discussed in this paper.
Three scaled mock-ups, which were modeled for reactor coolant system (RCS), reactor vessel (RV) and reactor vessel internal/control rod drive mechanism (RVI/CRDM), were prepared for these projects.
In our study, 3D-FE models have been developed for the RCS, RV and RVI/CRDM mock-ups, and time history response analyses have been performed for those 3D-FE models. The results are discussed in this paper.

Presenting Author: Yasutaka Kumagai Mitsubishi Heavy Industry

Presenting Author Biography: 2007 Mar M.S Osaka Electro-Communication University
2007 April I joined Mitsubishi Heavy industry
I am in charge of designing Reactor internal.

Authors:

Takehiro Kawashima Mitsubishi Heavy Industry
Yasutaka Kumagai Mitsubishi Heavy Industry
Yuki Asao Mitsubishi Heavy Industry
Shota Shimazu Mitsubishi Heavy Industry
Takuya Nishimura Mitsubishi Heavy Industry