Aerodynamic Load Variation and Wind-Induced Vibration Analysis of Tower Cranes Under Full Wind Angles

Abstract

When tower cranes are applied in coastal engineering, the wind-induced vibration under complex wind loads along the coast will be exceptionally obvious. It is increasingly important to explore the wind-induced vibration characteristics of different sections of tower cranes under full wind angles. This paper first establishes a three-dimensional numerical wind tunnel model that can be used for the simulation of tower cranes under full wind angles and analyzes the aerodynamic load variation of the tower crane under full wind angles. Secondly, the tower crane structure is divided into sub-regions, and the AR model method in the linear filtering method is used to simulate the three-dimensional wind speed time history. Further, the wind speed time history is applied to the finite element transient analysis, and based on the Newmark-beta method, the acceleration and displacement responses of different sections of the tower crane structure under fluctuating wind are systematically studied. Finally, the equivalent static wind load of different sections of the tower crane is evaluated by using the gust load factor method. The results indicate that the wind load of the tower crane exhibits an obvious three-dimensional effect, and the crosswind load cannot be ignored in the analysis of wind stability. The different sections of the tower crane structure show low-frequency vibration characteristics, and the low-frequency band is dominated by down-wind vibration, while the high-frequency band often experiences crosswind vibration. The amplification effect of the tower crane on fluctuating wind loads will increase with the increase of the height of the tower crane and the length of the jib, and the amplification effect on fluctuating wind loads in the crosswind direction is more obvious. The equivalent static wind load on the top of the tower crane reaches the maximum when the angle between the jib and the incoming wind is 60°.