This paper experimentally investigates the seismic behavior of a large-scale hollow-core fiber-reinforced polymer-concrete-steel HC-FCS column under seismic cyclic loading. The HC-FCS column consisted of a concrete shell sandwiched between an outer fiber-reinforced polymer (FRP) tube and an inner steel tube. The FRP tube provides continuous confinement for the concrete shell along the height of the column while the steel tube provides the required flexural strength. The tested column has an inner steel tube that had a diameter-to-thickness ratio (Di/t) (of 254. The seismic performance of the precast HC-FCS column was compared to that of HC-FCS column having(Di/t) of 64. Three-dimensional numerical models were also developed using LS_DYNA software for modeling the HC-FCS columns. This study revealed that HC-FCS columns having very high (Di/t) and short embedded lengths do not dissipate high levels of energy and display nonlinear elastic performance due to steel tube slippage. However, the use of small values of (Di/t)combined with generous embedment length results in a nonlinear inelastic behavior, high energy dissipation, and ductile behavior
