Krylov Subspace Model Order Reduction for FE seismic analysis

A model order reduction via Krylov Subspace (KS-MOR) is utilized into FE seismic analysis to reduce computational time. KS-MOR generates an effective set of orthogonal basis vectors that define the subspace. In this paper, the procedure of KS-MOR is introduced and a numerical example of 3D isolated bridge model was solved subjected to Kobe earthquake and Tohoku earthquake. The advantage of isolated bridge is clearly shown in the reduction of displacement at superstructure at high speed loading case (Kobe earthquake). In a case of low speed loading (Tohoku earthquake), seismic isolation bearing eliminates the high frequency oscillation. Both earthquakes loading case show deceasing of stress level.