Abstract:

As the conventional pushover procedure only considers the first-order vibration mode, this paper proposes a multi-mode pushover analysis （MPA） procedure based on the mode-superposition response spectrum method to consider the effect of high-order vibration modes. In order to impersonally evaluate the correctness of the proposed MPA procedure and the traditional pushover procedure, an incremental elasto-plastic time-history analysis is performed. Based on the analytical results and the fiber models of a six-storey and a ten-storey reinforced concrete frame, the two procedures in different lateral force modes are compared. The results indicate that, as compared with the conventional pushover procedure, the proposed MPA procedure gives more accurate predicted response of maximum elasto-plastic vertex displacement. However, the estimated accuracy of the maximum storey drift of the structure obtained by MPA procedure still needs to be improved.

Key words: static elasto-plastic analysis, elasto-plastic time history, multi-mode pushover analysis, reinforced concrete frame, fiber model