Vibration and damage detection in undamaged and cracked circular arches: Experimental and analytical results

This paper presents the experimental results of the dynamic behaviour of a circular arch in undamaged and several damaged configurations, and compares them with those obtained by means of analytical methods. The damage is introduced in the undamaged arch by operating a notch and is then modelled as a torsion spring of suitable stiffness localised in the damaged cross-section. Good agreement between analytical and experimental results is observed. An identification procedure based on frequency measurements is proposed and validated.