Analysis of segmental piers consisted of concrete filled FRP tubes

Precast segmental construction technique is an excellent candidate for economic rapid bridge construction in highly congested urban environments and environmentally sensitive regions. This paper presents three dimensional nonlinear finite element models using ABAQUS⧹Standard for evaluating the behavior of segmental precast post-tensioned piers under lateral loads. The piers were constructed by stacking precast concrete filled fiber reinforced polymer tube segments one on top of the other and then connecting the assembly structurally with vertical post-tensioning tendons passing through ducts located in the precast segments. A stress–strain relationship for confined concrete was used to model the concrete. The post-tensioning tendons were modeled with beam elements. The model was able to predict the backbone curves for two piers subjected to cyclic loads. A parametric study indicated that increasing the applied post-tensioning force increases nominal strength. Finally, the model showed that the pier aspect ratio, cross sectional diameter size, pier size, and confinement have significant effects on the performance of the investigated piers.

► Results confirmed that PPT-CFFT piers can effectively resist lateral forces.
► The level of the post-tensioning forces has significant effects on the backbone curves of PPT-CFFT piers.
► The pier size played an important role in the behavior of the pier once the interface joint opened.
► Increasing the FRP tensile strength improved the strength and post-elastic stiffness of the piers.
► Tendons in squat piers tend to yield at small drift angles compared to relatively slender piers.