Title: Seismic Performance of Precast Unbonded Prestressed Concrete Columns

Author(s): Ryo Yamashita and David H. Sanders

Publication: Structural Journal

Volume: 106

Issue: 6

Appears on pages(s): 821-830

Keywords: column(s); precast; prestressed concrete; seismic performance; shake table testing; unbonded

DOI: 10.14359/51663183

Date: 11/1/2009

Abstract:
Shake table testing and an analytical study were conducted to investigate the seismic performance of unbonded prestressed hollow concrete columns constructed with precast segments. A prototype column was designed based on the current bridge specifications by AASHTO. A one-fourth-scale model column was constructed by match casting. Shake table testing that consisted of 15 runs based on the 1995 Hyogo-Ken Nanbu (Kobe) Earthquake was conducted. The specimen performed very well with essentially no residual displacement and only limited concrete spalling at the base. A parametric study was conducted using a nonlinear twodimensional finite element pushover analysis. An equation to estimate the strain in the prestressing strands was proposed. A simplified method to calculate the load-displacement relationship showed good correlation with the pushover analysis results. Unbonded prestress columns can be designed to provide excellent drift capacity with limited permanent displacements.