Compared to typical buildings, pylons in cable-stayed and suspension bridges have a much higher slenderness ratio, requiring meticulous evaluation of wind loads. In particular, freestanding pylons before cable tensioning exhibit lower structural damping than after the cables are tensioned and are therefore more susceptible to wind-induced vibrations. Aeroelastic testing of pylons involves the use of a scaled elastic model that simulates the dynamic characteristics of the pylon—such as mass, natural frequency, damping, and vibration modes. In contrast, when the purpose is to evaluate wind loads acting on the pylon, two aerodynamic force tests are conducted using rigid-body models simulating entire pylon body and section model simulating pylon legs, respectively.

▣ Aerodynamic stability: vortex-induced vibration, flutter, galloping
▣ Base shear force, base overturning moment, base torsional moment
▣ Wind force of pylon legs: Drag, lift, pitching moment coefficients
▣ Wind force of whole pylon: Drag, lift, torsional moment, overturning moment coefficients
▣ Aerodynamic optimization of the shape of pylon leg to increase aerodynamic stability and to decrease static deformation due to wind