An Improved Multimodal Procedure for Deriving Pushover Curves for Bridges

Abstract eng:
A modal pushover analysis (MPA) procedure for bridges is first proposed, that involves two additional steps compared to the initial proposal of the writers (Paraskeva et al, 2006), the key idea being that the inelastic deformed shape of the structure subjected to the considered earthquake level is used in lieu of the elastic mode shape. The concept of a multimodal pushover curve (derived using the MPA procedure) in terms of the base shear vs. deck maximum displacement is then put forward. The improved MPA procedure is used to assess the seismic performance of two actual bridges. The first structure is the Krystallopigi bridge, a 638m-long multi-span bridge, with significant curvature in plan, unequal pier heights, and different types of pier-to-deck connections. The second structure is a 100m-long three-span overcross bridge, typical in modern motorway construction in Europe, which is found to exhibit a rather unsymmetric response in the transverse direction, mainly due to torsional irregularity. It is found that the multimodal pushover curve reasonably matches the dynamic pushover curve derived from the more rigorous NL-RHA procedure. On the other hand, standard pushover curves based on single modal patterns, underestimated the total base shear and stiffness of the studied bridge.

• Export as: BibTeX | MARC | MARCXML | DC | EndNote | NLM | RefWorks
• Add to your basket