Statics and dynamics of tall guyed radio navigation towers

The purpose of this research was to study the static and dynamic behavior of tall guyed radio navigation towers in order to evaluate the feasibility of using vibration analysis as a means to determine the tensions in the guy wires and to identify the presence of structural defects in the tower. The static response of guy wires was studied as a precursor to the dynamic response. Results of a detailed experiment on a scale model guy wire corresponded with predictions from the equations of the elastic catenary within {dollar}pm{dollar}6%. The dynamic response of guy wires was studied and the results of a detailed experiment on a scale model guy wire compared with theoretical predictions for natural frequencies with an average difference of 0.7%. The experimental results showed hybrid mode shapes and gave clear evidence of avoided crossings in the natural frequencies. The theoretical results indicated that the accuracy of the curvature term has a profound impact on the accuracy of the solutions. The tension at the base of the scale model guy wire was determined within 2.5% by correlating experimentally measured natural frequencies with theoretical predictions. It was determined that a useful tool could be made which would allow for determination of the tension at the base of a full size guy wire by measuring the guy wire vibrations. The dynamic response of a model guyed tower was studied. It was determined that the proposed method of vibration analysis would not provide a useful means of identifying small structural defects in tall guyed radio navigation towers.