Use of ambient response measurements to determine dynamic characteristics of slender structures

This paper deals with the experimental studies for determining the dynamic characteristics of slender structures by using the measured structural responses to ambient excitations e.g. traffic excitation or wind load. The theoretical background for random response of linear structures, the experimental method, data acquisition and analysis techniques for identifying the characteristics of the structures are expounded. On-site measurements of a 30 m tall lamp post structure under ambient ground motion and the excitation of wind of Beaufort force 6 were carried out. Natural frequencies and the correspondent modal shapes are obtained.