Shaking Table Testing of Segmental Hollow-Core FRP-Concrete-Steel Bridge Columns

Abstract

This article presents dynamic tests of three damage-resistant segmental hollow-core bridge columns with posttensioned unbonded strands. One column was constructed without energy dissipaters, whereas the other two columns included different external energy dissipaters. A reference RC column was also investigated. The cross section of the segmental columns was a hollow-core section composed of an outer glass-fiber-reinforced polymer (GFRP) shell, an inner steel tube, and concrete shell cast in between the GFRP shell and the steel tube. The columns combine the advantages of accelerated bridge construction and self-centering as a result of rocking with high energy dissipation from the external energy dissipaters. All columns were subjected to a sequence of scaled near-fault pulse-like ground motions. The well-designed hollow-core segmental column sustained no noticeable damage and no residual drift after a sequence of motions up to 250% of the design earthquake, which caused a peak drift ratio of 8.85%. Conversely, the counterpart conventional column suffered severe damage, with rebar fracture and extensive concrete spalling. The accumulated residual drift of the conventional column was 1.5% after the sequence of motions up to 200% of the design earthquake, which caused a peak drift ratio of 4.8%. The energy dissipated by the segmental columns with external energy dissipaters was comparable to that of the conventional RC column along the tests.