PSI - Issue 5

Baris Arslan et al. / Procedia Structural Integrity 5 (2017) 171–178 Baris Arslan et al. / Structural Integrity Procedia 00 (2017) 000 – 000

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6

3.2. Mechanical Impedance

The method for the mechanical impedance computation is associated with mass, stiffness and frequency. Considering sinusoidal driving force (F) which has a magnitude of F 0 and angular frequency of ω; 0 j t F F e   5

The application of this force to a linear mechanical system results in velocity;

( 0 j t v v e     )

6 Where; 0 v is the magnitude of the velocity and φ is the phase angle between F and v. Thus; MIS of structural system m Z at the point of application of the force is given by;

m Z F v 

7

In this study, in order to investigate the MIS results, the corner node of the PZT patch which is situated on the tie constraint between the PZT patch and the concrete, is selected. Nodal forces and the velocities which are on the polarization direction of the PZT patch are obtained and arranged according to Eq.7. Results are plotted in Fig. 4.

Fig 4.a Freq between 0-2000 Hz

Fig 4.b Freq between 2000-4000 Hz