Parametric Investigation of Bridge Piers Reinforced with Shape-Memory Alloys in Plastic Hinge Regions

Abstract

AbstractBridge piers are one of the most vulnerable structural elements in a bridge system. The past earthquake reconnaissance report showed that the bridge structures with high residual displacements were unserviceable for the future use after a seismic event. Subsequently, post-disaster rescue and relief operations were rigorously affected. Generally, it is presumed that the utmost seismic demand in a bridge will focus in a small zone, which has a maximum inelastic curvature called as its plastic hinge length. As the bridge pier’s plastic hinge zone governs the load carrying and deformation capabilities of the entire pier, hence it has achieved remarkable focus to structural designers for the last decades to improve the ductility of a pier. Shape memory alloy (SMA) is distinctive class of smart materials, which can sustain the enormous amount of inelastic deformations and reappear to its parental shape after removal of stress or loading. Substituting the typical steel reinforcement in the plastic hinge region of a bridge pier with super-elastic SMA could diminish the damages of a pier. The present research is focused on the numerical investigation on circular concrete bridge piers reinforced with SMA rebars in plastic hinge region and rest part of a pier reinforced with conventional steel under the effect of monotonic static loads. The parameters considered in this study are plastic hinge length and material properties of SMA. Nonlinear static pushover analysis is performed to compare the behavior of steel-RC and SMA-RC bridge piers under the effect of monotonic load. The results are presented in terms of base shear, displacement, ductility and limit state performance criteria of bridge piers. KeywordsShape-Memory AlloyPlastic hinge length Bridge piersStatic pushover analysis