MAST VIBRATION ANALYSIS

The work shown here is reproduced by kind permission of London Offshore Consultants Ltd.

The work exampled here was carried out for Platinum Yaughts. The foremast and main masts were modelled with their foundation stuctures. Eigen Mode (frequency analysis) was then undertaken to establish the various harmonic frequencies of the masts. These modes were then compared with other known forcing frequencies such as:

Engines
Propeller
Generators
Thrusters

When the forcing frequencies match the harmonic frequency of any of the Eigen frequencies - then resonance and dynamic amplification would occur.

As a result of this study further pipe supports were added to the inside of the foremast and the main platforms of the main mast were subsequently foam filled. These measures were then proven, through further analysis, to be sufficient to prevent the unwanted resonance.