engleski

Damage detection of plate like structures based on changes of basic modal parameters

Damage detection of structures is one of the essential parts of structural health monitoring. Damage is defined as a change in structure which affects its future behaviour. This paper pre- sents the problem of damage identification of plate like structures regarding material and ge- ometric properties. It is possible to identify damage of structure by comparing basic modal parameters of its two states: undamaged and damaged state. Basic assumption is that the damage changes structures physical properties such as stiffness and/or mass which causes changes of modal parameters: natural frequencies, modal shapes and damping coefficients. The purpose of this investigation is to detect damage on simply supported full-scale rein-forced concrete plate like structure. Using saw cutting method discrete or continuous damag-es were applied to the compression zone of the plate. Using dynamic parameters it is possible to detect the existence of damage in the first step and, furthermore, evaluate the location and severity of the damage in the second step. Vibration responses are acquired by a number of transducers and their arrangement is changed during different stages of experimental testing. Vibration induced using impact hammer were used for the excitation. Dynamic parameters are obtained using Operational Modal Analysis. The numerical and experimental damage de-tection on the reinforced concrete plate were carried out and the obtained results compared.

Damage ; detection ; plate ; structures ; vibration ; modal shapes

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