PSI - Issue 70

Maheshwari Sonker et al. / Procedia Structural Integrity 70 (2025) 477–484

480

Portable computer

Concrete Cube

PZT sensor bonded at surface

M65

Impedance analyser

M60

Cable-wire

Fig. 2. Setup for recording the admittance signature acquisition of concrete cubes. 3.1 Induced Structural Damage and EMI Characterization through Conductance Response Analysis A comparative examination of conductance (real) signatures reveals a progressive deviation from the baseline, correlating with an increase in damage of depth up to 12 mm. In the standard 150 × 150 × 150 mm concrete cube, cracking initiates near the surface-mounted PZT sensor, positioned at distances of 50 mm and 100 mm from specimen corner. Initially, 6 mm deep cracks are introduced at the 50 mm mark, followed by the acquisition of conductance versus frequency data. Subsequently, additional cracks are induced at the 100 mm interval, with crack depths extending to 8 mm and 12 mm, resulting in corresponding shifts in conductance signatures, which are continuously monitored. As damage severity increases (6 mm, 8 mm, and 12 mm depths), the conductance signature shifts leftward, indicating greater damage. The shifting extent varies with damage level, with further leftward shifts for damage exceeding 12 mm, as shown in Fig.3. Impedance signatures were separated into conductance (real) components. Observed shifts in peak positions and amplitude suggested changes in local mechanical properties.

1.99E-03

M60

1.79E-03

1.59E-03

baseline state CUT-1_6mm CUT-2-6mm CUT-1_8mm CUT-2-8mm CUT-1_12mm CUT-2-12mm

1.39E-03

1.19E-03

Conductance G

9.90E-04

7.90E-04

138000 148000 158000 168000 178000 188000 198000 208000 218000 228000

Frequency (Hz)