EARTHQUAKE RESISTANCE EVALUATION METHOD OF STEAM GENERATOR

PROBLEM TO BE SOLVED: To enable a highly accurate earthquake resistance evaluation to be performed in consideration of elastoplasticity simply in a short time and capable of achieving elaboration of an evaluation method.SOLUTION: In step S1, a detailed analysis model is prepared by combining components of an U bend part based on drawing data. In step S2, an eigenvalue analysis is performed by a detailed analysis model so as to obtain mode information of the U bend part. In step 3, an intrinsic mode of a frequency area large in response is specified by an earthquake response spectrum from mode information obtained by an intrinsic value analysis result in step 3. In step 4, elastoplasticity characteristics are set to the detailed analysis model. In step 5, a static analysis is performed using the detailed analysis model. In step 6, load displacement characteristics acting on the U bend part are obtained from a static analysis result. In step 7, a simple model of a 1 freedom degree system is prepared from a mode mass of the intrinsic mode and the load displacement characteristics. In step 8, a response waveform is obtained from an earthquake wave time history response analysis. In step 9, an ultimate strength evaluation is performed using the response waveform.