Wind-induced buffeting comfort assessment of tower cranes considering the wake effect of super-high bridge towers

The buffeting analysis of tower cranes lays a solid foundation for the occupant comfort assessment under the construction stage. However, the aerodynamic characteristic of the crane outer-attached to bridge pylons with variable cross-sections is usually complex, making it hard for accurate buffeting comfort assessment of cranes. An architecture of buffeting analysis of tower cranes is proposed by modifying Davenport quasi-steady buffeting forces for cranes considering the variation of aerodynamic sections of pylon-crane systems. The dimensions of pylons along the height and the distance of the upper flexible crane from its adjacent pylon are the dominated factors on this section-varying system. A series of CFD simulations are implemented to investigate the along-wind force coefficient of the crane for various aerodynamic sections of the system. Based on the obtained force coefficients related with the height and distance, the modified buffeting force is calculated by the Restart technology of ANSYS. The effectiveness of the proposed architecture is proved by the time-domain buffeting analysis of the pylon-crane system. The buffeting comfort assessment of the tower crane is implemented by constructing comfort envelops with reference wind velocities under different comfort acceleration thresholds.