Dynamic/earthquake analysis - Computational Analysis and Design of Bridge Structures - page 542

Pushover curve (Figure 17.21) uses mode 2 as the lateral load (mode
shape as shown in Figure 17.22 multiplied by the mass). NL-THA was per-
formed using three different acceleration histories, and average response
was compared with those from the modal pushover analysis.
Peak ground accelerations (PGAs) of 0.30 g and 0.45 g were considered.
Comparison is performed for the maximum demand displacement in the
transverse direction, total base shear, and rotations of plastic hinges. Results
of the standard and modal pushover approaches were evaluated by compar-
ing them with those from the NL-THA; the latter is considered to be the

Base shear—Displacement

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Displacement (in)

Figure 17.21 Pushover curve using mode 2 as the lateral load.

Figure 17.22 Deformed shape of mode 2 ( T 2 = 0.5621s).