Stockbridge damper

Aeolian vibration occurs in the vertical plane and is caused by alternating shedding of vortices on the leeward side of the cable.

A steady but moderate wind can induce a standing wave pattern on the line consisting of several wavelengths per span.

[5] Live-line working using hot stick tools meant it was possible to retrofit dampers to lines while energised.

[7] To provide for greater freedom of motion, the weights may be partially slotted in the vertical plane, allowing the cable to travel outside the confines of the bell.

Some more complex designs use weights with asymmetric mass distribution, which enables the damper to oscillate in several different frequency modes and ranges.

This is common when the cable runs in a vertical or off-horizontal plane, for example in cable-stayed bridges or radio mast guy-wires.

An example photo of Stockbridge dampers hanging under-slung from high voltage wires
Stockbridge dampers installed on high voltage power lines
Stockbridge's original concrete block design
A modern design with metal weights
Dogbone dampers on the road-support cables of the Severn Bridge