大きな地震荷重下での配管系の弾塑性応答と疲労破損についての解析評価(J18-1 解析・設計の高度化・最適化(1),J18 解析・設計の高度化・最適化)

Abstract

The seismic shaking test of a large-scale piping system with a piping bore of 200A and made from carbon steel material was conducted. Two test models were used, one for the design method confirmation test and one for the ultimate strength test, For the ultimate strength test, a series of tests was initiated at a pseudo-elastic design stress level of about 9 times the current allowable primary stress limit (3Sm) for the "S_2" seismic wave, being repeated until the occurrence of piping failure due to through-wall fatigue cracking with ratcheting deformation was obtained during Run 5, of seismic shaking. Post-test analysis results, which were obtained in two steps, compare well with the ultimate strength test results of elasto-plastic global response, local strain and the number of runs to piping failure. In step 1, the elasto-plastic response analysis of the whole model was performed, using elbow element and linear kinemateic hardening rule. In step 2, the local strain behavior of Elbow2 was calculated by forced displacement analysis, using shell element and non-linear kinemateic hardening rule (AF-OW), and the fatigue damage accumulation coefficient was calculated.