Effects of bridge curvature radius on results of nonlinear dynamic analysis in coastal curved bridges

One of the methods that has appropriate accuracy, applicability and reliability and will be discussed in this study is the Bidirectional Energy Based Pushover (BEP) method. Because the capacity curve obtained from BEP is unique and the main parameters of the pusher (load pattern, control point and monitor point) cannot question the accuracy of this approach; because there is no need to select a point monitor to obtain the capacity curve and instead, all the monitor points must be displaced to calculate the energy absorbed in the pusher stage. This method has been evaluated in terms of accuracy and applicability in building structures. This is while the aim of this study is to extend this method to assess the seismic vulnerability of bridges with curvature in plan.After identifying and selecting the methods and models considered for each element, and considering the defined uncertainties, the proposed models are modeled in OpenSeesPy software to perform IDA analysis. In order of material behavior, concrete, steel, geometry and modeling details, boundary conditions are selected based on previous studies, and modeling is performed accordingly. In this paper evaluated the effects of radius of curvature on the seismic response of curved bridges. For ۴-span bridges, the weak and strong earthquake errors increase with increasing radius of curvature. However, for ۲-span and ۳-span bridges, the curved bridge with a radius of ۴۲۰ m in two spans and the curved bridge with a radius of ۱۰۰۰ m in three spans experienced lower average errors in very strong motions (۸۴th percentile) than the other curves. This indicates that the effect of curvature on accuracy depends on the bridge configuration. The errors between the BEP curve and the accurate IDA vary depending on the earthquake magnitude (percentiles). Weaker and stronger earthquakes (۸۴th and ۱۶th percentiles) generally showed higher errors compared to moderate intensity (۵۰th percentile).

Keywords:

Seismic vulnerability , curved bridges , Curvature radius , BEP analysis , IDA