Conductor vibration - theoretical and experimental investigations on a laboratory test span

The behaviour of a test span, artificially excited into transverse vibration, is studied. The decay mechanism is particularly analysed. It is shown that the decay is of the form of a step curve. The phenomenon is found to appear markedly in highly damped spans, but may be easily overlooked if the damping is small. Damping measurements in a laboratory test span by using the decay method are discussed. It is shown that the commonly used logarithmic decrement does not give significant information on the performance of a vibration damper. From the equations given in the paper, it is possible, from decay measurements, to calculate the power consumption which is recommended as a measure of damper efficiency.