Seismic Behavior of FRP-High-Strength Concrete–Steel Double-Skin Tubular Columns

Abstract

AbstractThis paper reports on an experimental study on the seismic behavior of fiber-reinforced polymer (FRP)–concrete–steel double-skin tubular (DST) columns. Nine DST and one concrete-filled FRP-tube (CFFT) columns that were made of high-strength concrete were tested under constant axial compression and reversed-cyclic lateral loading. The main parameters of the experimental study were axial load level, amount and type of FRP confinement, concrete strength, sectional shape and thickness of the inner steel tube, and provision (or absence) of a concrete filling inside the steel tube. Of primary importance, the results indicate that DST columns are capable of developing very high inelastic deformation capacities under simulated seismic loading. The results also indicate that the presence of a concrete filling inside the inner steel tube significantly and positively influences the seismic behavior of DST columns. It is found that the performance of the void-filled DST column is superior to that of a compani...