Theoretical-Experimental damage determination in prestressed concrete beams

DANIEL AMBROSINI, RICARDO; LUCCIONI FORNS, BIBIANA MARÍA; DANESI, RODOLFOFRANCISCO

The e-Journal of Nondestructive Testing

UFSM

Lugar: Santa María; Año: 2000 vol. 5 p. 1 - 5

1435-4934

The dynamic properties of engineering systems are modified by the presence of structural damage. Changes in a structure are made evident by modification of the modal parameters such as natural frequencies, modes of vibration and modal damping. All this parameters can be obtained from dynamic tests. Experimental results of a prestressed concrete beam are presented in this paper. Damage due to corrosion of the reinforcement was simulated by the progressive cut of the prestressing bars until 50% of them. The beam was tested under flexion exceeding the cracking load and, thus, concrete was also damaged. For each load step, natural frequencies and modes of vibration were measured. In based of these values, a correlation between changes in dynamic parameters and damage produced can be formulated. On the other hand, a numerical computational analysis was performed in order to validate frequencies and modes of vibration registered.