Optimization of embedded piezoelectric transducers for shear wave velocity measurements

Context of the master thesis

The mechanical properties of concrete are commonly measured using static traction/compression tests following different available standards. Such tests require to have access to an adequate testing machine and to design a specific concrete sample with given shape and dimensions. An alternative is the use ultrasonic methods which are much easier to implement. They consist in measuring both the traction-compression (P-wave) and the shear (S-wave) velocities in the concrete specimen from which the Young’s modulus and the Poisson ratio can be computed. At BATir-ULB, we have developed embedded piezoelectric sensors for ultrasonic testing of concrete. These have been used to measure the traction-compression wave velocity (P-wave) [1]. They have been designed and optimized through numerical calculations using the finite element method [2]. Our aim is to design new transducers to measure the S-wave velocity.

 References

[1] Dumoulin C., Karaiskos G., Carette J., Staquet S. and Deraemaeker A.. Monitoring of the ultrasonic P-wave velocity in early-age concrete with embedded piezoelectric transducers. Smart Materials and Structures, 21(4), (2012)

[2] C. Dumoulin and A. Deraemaeker. Design of embedded piezoelectric transducers for structural health monitoring in concrete structures. In EWSHM 2016, Bilbao, Spain, July 2016

The objective of the thesis is to design and optimize embedded piezoelectric transducers for S-wave actuation and sensing in concrete. The work consists in using an existing software developed under Matlab. It consists in a finite element package (the Structural Dynamics Toolbox) and optimization routines based on a genetic algorithm. This existing software has already been used for the design of the P-wave transducers, and the work consists in taking advantage of this tool to design shear-type embedded piezoelectric transducers for wave actuation and sensing in concrete.

Arnaud Deraemaeker (aderaema@ulb.ac.be)

Co-Supervisor

Cédric Dumoulin (cedumoul@ulb.ac.be)

English/French

Architectural Engineering/Civil Engineering/Mechanical Engineering

The student must have an interest in Structural Dynamics, the finite element method, basic programming skills in Matlab .