Due to the swirl-excited transverse vibrations, large base moments can occur in the support area. Unanchored constructions can be in danger of tipping in the assembled state. If this is the case, it must be ensured for this construction phase by weather forecasts that the critical wind speed at which the transverse vibrations can occur is not reached for the period of the hazardous installation section.
One way of temporarily or permanently preventing lateral vibrations without having to change the main load-bearing structure is to install aerodynamic interference measures in the area of the effective length of the lateral vibrations. The so-called vortex removers are profiles that are placed in the upper part of the structures to prevent the vertebrae from continuously loosening over the height. They ensure that the flow is detached in different directions, so that there is no alternating separation.
An example of such solutions for towers/chimneys is the SCRUTON coils, which are used most frequently. These are three-way fault bars (no lattice strips), which are often installed helix-like around the structure in the upper third.