The study on the vulnerability of the concrete stilled steel tubular frame with buckling-restrained braces structure under the coupling of wind and earthquake

During their service periods, engineering structures may inevitably be subjected to multiple natural hazards, such as winds and earthquakes. The vulnerability of a concrete filled steel tubular frame with buckling-restrained braces under the coupling of wind and earthquake is investigated. The wind speed time histories at different heights of the structure are simulated by assuming the return period to be 1 year, 10 years and 50 years, respectively. The OpenSees platform is employed to develop the finite element model of the considered structure. Nonlinear time history analyses are performed for the structural numerical models under four cases, namely the separate earthquake excitation, simultaneous earthquake and wind with return periods of 1 year, 10 years and 50 years, respectively. Fragility curves under different cases are generated based on the probabilistic seismic demand analysis. The numerical results show that the structural response and the vulnerability increase gradually with the wind speed, while the influence of the wind loads decreases with the increase of the intensities of input seismic motions. © 2019, Editorial Office of China Civil Engineering Journal. All right reserved.