This seminar is intended to evaluate the applicability of Nonlinear Static Procedure by implementing the Displacement Coefficient Method to bridges. For comparison purposes, the Nonlinear Dynamic Procedure (or nonlinear time-history analysis), which is considered to be the most accurate and reliable method of nonlinear seismic analysis, is also performed. A three-span bridge of 97.5 meters (320 ft) in total length was analyzed using both the Nonlinear Static Procedure/Displacement Coefficient Method and nonlinear time-history. Nine time-histories were implemented to perform the nonlinear time-history analysis. Three load patterns were used to represent distribution of the inertia forces resulting from earthquakes. Demand (target) displacement, base shear, and deformation of plastic hinges obtained from the Nonlinear Static (Pushover) Procedure are compared with the corresponding values resulting from the nonlinear time history analysis. Analysis was performed using two levels of seismic load intensities (Design level and Maximum Considered Earthquake level). Performance of the bridge was evaluated against these two seismic loads. Comparison shows that the Nonlinear Static Procedure gives conservative results, compared to the nonlinear time history analysis, in the Design Level while it gives more conservative results in the Maximum Considered Earthquake level.
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