Prestressed precast concrete columns are recently considered as excellent design options due to their self-centering capability for seismic actions. Axial prestressing is designed to control cracking at the precast joints by service loads. In this paper, a combination of continuous reinforcing bars and prestressing tendons was suggested to enhance seismic performance as well as economy of precast piers. Cyclic tests were conducted to verify the suggested concept. By preventing buckling and fracture of the reinforcing bars in the plastic hinge region, the test specimens showed remarkable ductility without reduction of their flexural strength. Appropriate magnitude of initial prestressing force was also proposed to prevent fracture of tendons by large lateral deformation of columns in strong earthquakes.
In this paper, a design concept of post-tensioned precast bridge piers was proposed to improve seismic behavior of the bridge pier. Mild reinforcing bars are placed continuously along the height of the column. Prestressing tendons are also provided to obtain re-centering capability for seismic events. Arrangement of the axial steels to prevent buckling of rebars at plastic hinge region was suggested and enhanced seismic performance was verified by experiments. Moment-curvature analyses were performed to evaluate the effect of effective prestress on seismic behavior after verifying the calculation method by cyclic tests of the precast columns. A real bridge pier was designed to investigate the seismic performance according to different level of effective prestress. Level of effective prestress showed obvious effect on crushing displacement but negligible effect on lateral displacement at fracture of tendons and reinforcements.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.