Dynamic Buckling and Nonlinear Response of Fast Breeder Reactor Main Vessels under Earthquake Loading

Abstract

Pseudodynamic tests of cylindrical shells under high temperature were performed in order to study elasto-plastic shear-bending buckling and the nonlinear response of fast breeder reactor (FBR) main vessels under earthquake loading. The test results showed a response reduction effect due to pre-buckling plasticity and a large seismic margin, which is the difference in seismic excitation amplitudes between the earthquake design conditions and the ultimate state, and is attributed to the energy absorption of the cylinders before and after buckling. A simple expression of the response reduction effect was proposed, as a contribution to the safe and effective seismic design of FBRs. A seismic margin evaluation method was also proposed, and it was shown that appropriate seismic margins can be ensured when the response reduction effect is incorporated into seismic design.