Title:
Seismic Behavior and Design of Reinforced
Concrete Columns Confined with FRP
Stay-in-Place Formwork
Author(s):
M. Saatcioglu, T. Ozbakkaloglu, and G. Elnabelsy
Publication:
Symposium Paper
Volume:
257
Issue:
Appears on pages(s):
149-170
Keywords:
concrete confinement; concrete columns; carbon fiber-reinforced polymer
(CFRP); displacement-based design; ductility; earthquake-resistant design; fiberreinforced polymer (FRP); stay-in-place formwork
DOI:
10.14359/20245
Date:
10/1/2008
Abstract:
One of the applications of fiber-reinforced polymers (FRP) in building and bridge construction is stay-in-place formwork. FRP stay-in-place formwork, in the form of preformed tubes, provides easy form assembly protection of steel reinforcement and concrete against corrosion and chemical attacks while also improving the strength and ductility of structural elements in earthquakeresistant construction.
Seismic performance of FRP tubes in building and bridge columns has been investigated through tests of large-scale specimens under simulated seismic loading. The experimental program consisted of tests of circular and square columns confined with carbon FRP (CFRP) tubes. The results indicate that
the use of CFRP tubes increases column inelastic deformability significantly. Bridge columns under low levels of axial compression exhibit inelastic drift capacities in excess of 4% before failing in flexural tension due to the rupturing of longitudinal reinforcement. Building columns under higher levels of axial compression show drift capacities in excess of 8% when the behavior is governed by confined concrete. These observations and experimental results were used to develop a displacement-based design procedure for concrete confinement for FRP-encased concrete columns. The paper presents an
overview of the experimental program and the design approach developed.