Using Ambient Vibration Measurements (AVM) and Operational Modal Analysis (OMA) to Characterize Telecommunication Monopoles
Received Date: August 09, 2019; Published Date: September 03, 2019
This paper presents the dynamic characteristics of 20 steel telecommunications monopoles as extracted from ambient vibration measurements made directly on the base and on the structure itself at low height. Velocities are measured during a minimum of 30 minutes at each site with highly sensitive micrometers, synchronously at the different positions. The records are analysed using a frequency domain decomposition algorithm available in commercial software. Statistical analysis of the extracted results indicate that the fundamental natural frequencies could be identified with high precision (standard deviation less than 4%) while the corresponding total equivalent damping was less precise, with standard deviations between 6 and 28%. The low-cost, non-intrusive AVM tests are deemed appropriate to evaluate the vulnerability of telecommunications monopoles to wind-induced instabilities.