Research on Collapse Mechanism and Failure Criterion of Superlarge Cooling Tower under Downburst Effect

The world's highest cooling tower (228 m), which is under construction in Northwest China, was chosen to study the response characteristics and collapse mechanism of a superlarge cooling tower under the downburst effect. A structural multiscale finite-element model was constructed using the layered shell element method. Fluctuating wind pressures on the internal and external surfaces of the superlarge cooling tower at four typical working conditions under the downburst effect were obtained based on large-eddy simulation (LES). The variation laws of the wind-induced collapse of superlarge cooling tower were analyzed using incremental dynamic analysis. The collapse mechanisms of the superlarge cooling tower under downburst effect were determined. The collapse failure criterion of the superlarge cooling tower under the downburst driving effect were established. Results demonstrated that the wind pressure distribution mode on the tower body surface under downburst was significantly different from that under normal wind. The collapse mechanism of the superlarge cooling tower changed from an inward mechanism to an outward mechanism with the increase of the distance to the downburst center. When the energy failure criterion index was K >= 2, the superlarge cooling tower collapsed. (C) 2022 American Society of Civil Engineers.