Acoustoelastic-Based Stress Measurement Utilizing Low-Frequency Flexural Waves Conference Paper uri icon

abstract

  • Current acoustoelastic-based stress measurement techniques operate at the high-frequency, weakly-dispersive portions of the dispersion curves. The weak dispersive effects at such high frequencies allow the utilization of time-of-flight measurements to quantify the effects of stress on wave speed. However, this comes at the cost of lower sensitivity to the state-of-stress of the structure, and hence calibration at a known stress state is required to compensate for material and geometric uncertainties in the structure under test. In this work, the strongly-dispersive, highly stress-sensitive, low-frequency flexural waves are utilized for stress measurement in structural components. A new model-based technique is developed for this purpose, where the acoustoelastic theory is integrated into a numerical optimization algorithm to analyze dispersive waves propagating along the structure under test. The developed technique is found to be robust against material and geometric uncertainties. In the absence of calibration experiments, the robustness of this technique is inversely proportional to the excitation frequency. The capabilities of the developed technique are experimentally demonstrated on a long rectangular beam, where reference-free, un-calibrated stress measurements are successfully conducted.

name of conference

  • ASME 2017 Conference on Smart Materials, Adaptive Structures and Intelligent Systems

published proceedings

  • Volume 2: Modeling, Simulation and Control of Adaptive Systems; Integrated System Design and Implementation; Structural Health Monitoring

author list (cited authors)

  • Albakri, M. I., Malladi, V., & Tarazaga, P. A.

citation count

  • 1

complete list of authors

  • Albakri, Mohammad I||Malladi, Vijaya VN Sriram||Tarazaga, Pablo A

publication date

  • September 2017