Sensor Size Effect on Rayleigh Wave Velocity on Cementitious Surfaces.
Nicolas Ospitia1, Dimitrios G Aggelis1, Gerlinde Lefever1
1Department of Mechanics of Materials and Constructions (MeMC), Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium.
Sensors (Basel, Switzerland)
|October 13, 2021
Summary
Sensor size significantly impacts ultrasonic surface wave velocity measurements in concrete. This study reveals the aperture effect on velocity and provides guidelines for accurate concrete property assessment.
Area of Science:
- Civil Engineering
- Materials Science
- Non-Destructive Testing
Background:
- Ultrasonic testing is crucial for evaluating concrete properties and damage.
- Single-surface access necessitates understanding the "aperture effect" related to sensor size.
- The aperture effect on surface wave velocity in concrete remains understudied.
Purpose of the Study:
- To investigate the influence of sensor size on surface wave velocity measurements in concrete.
- To analyze the dependence of surface wave velocity on frequency (dispersion) and sensor size.
- To establish guidelines for reliable ultrasonic measurements of concrete properties from a single surface.
Main Methods:
- Numerical simulations were performed using sensors of varying sizes.
- Surface wave velocity and dispersion were measured in simulations.
- Experimental validation was conducted on a cementitious material with different sensor sizes.
Main Results:
- A significant aperture effect was observed on surface wave velocity measurements.
- The study quantified the relationship between sensor size, frequency, and measured velocity.
- Numerical trends were successfully validated by experimental data.
Conclusions:
- Sensor size critically affects ultrasonic surface wave velocity measurements in concrete.
- Understanding and accounting for the aperture effect is essential for accurate concrete assessment.
- The findings provide practical rules for reliable single-surface ultrasonic testing of concrete.
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