Curved Continuous Rigid Frame Bridges with Initial High Pier Imperfections at the Largest Cantilever Stage: Geometrically Nonlinear Stability

Chatuluka, Quasshie

pages:1-13

We examined the geometrically nonlinear stability (GNS) of curved continuous rigid frame bridges (CRFB) at the biggest cantilever stage when the pier flaws were initially substantial. For models in an ideal state, initial tilt state, initial bend state, initial material imperfection state, or with various pier types, the stability safety factors were calculated and compared. When geometrically nonlinear influences are taken into account, the stability safety factors diminish. This decrease is more pronounced when the original material flaw manifests in the middle and lower sections of the pier. Stability is further reduced by a cross section in the double-limb piers. In fact, it is essential to minimize initial bend in order to guarantee a safe structure. Both start tilt and initial bend significantly affect stability, particularly the latter. Whether a single-limb or double-limb pier is used, these elements have an almost equal impact on stability. All of these findings point to the need for GNS analysis in order to properly evaluate the safety of a curved CRFB with high piers.

Keywords: Curved continuous rigid frame bridge (CRFB), high pier, geometrically nonlinear analysis (GNS), stability safety factor, finite element (FE) method, initial imperfections.