NUMERICAL SIMULATION OF TRANSIENT WAVES REFLECTED BY SURFACE BREAKING CRACKS IN CONCRETE

In the present work, a frequency domain Boundary Element Method in conjunction with the Fast Fourier Transform is employed for the numerical simulation of transient pulses interacting with surface breaking cracks in concrete. The goal is the development of a powerful and reliable numerical tool, capable for per-forming extensive parametric studies in non-destructive testing, which otherwise would be expensive and very time consuming to be conducted. The incident wave is considered to be a narrow band disturbance generated by an acoustic emission transducer placed near to the crack. The crack is simulated by a very thin open trench, which in cases of repaired cracks is partially or fully filled by resin. The obtained results are compared with experimental ones and the high accuracy of the proposed here numerical technique is demonstrated and assessed.