Experimental and numerical investigations on cyclic behaviors of precast segmental bridge piers with the hybrid of high-strength bars and unbonded prestressing tendons

Abstract

Precast segmental piers are gaining increasing attentions in low-medium seismic-risked regions. In this paper, cyclic behaviors of two precast segment piers reinforced with the hybrid of high-strength energy dissipation (“H” ED, ≥500 MPa) bars and unbonded tendons were experimentally investigated, accompanied with another two piers reinforced with merely “H” ED bars for the comparative study. It was observed that unbonded tendons benefitted the segmental piers in rising the lateral strength and mitigating the residual drift. On the other aspect, the tendons also made concrete prone to damage. Alongside, the finite element (FE) model is constructed for the four tested segmental piers, discritized with the displacement-controlled beam-colum element with a fiber section. With the bond-slip behavior of the “H” ED bars being incorporated, the numerical model accurately reflects the piers’ seismic behaviors.