Funding:

• • National Science Foundation

  • Department of Transportation/Federal Railroad Administration

  • Federal Aviation Administration

Synopsis:

The prediction of guided wave scattering behavior from material or geometrical discontinuities in a waveguide is of great importance in many fields. One application is quantitative NDT or SHM, where the goal is to identify the type and size of damage being detected in an ultrasonic guided wave test. Achieving this goal requires a sophisticated model. UCSD is utilizing a Global-Local approach to solve guided-wave scattering problems whereby the entire waveguide ("global" portion) is efficiently modeled by a SAFE analysis (cross-sectional FE discretization only) and the scatterer ("local" portion) is modeled by a full (2D or 3D) FE discretization. Continuity of displacement and stresses is imposed at the boundaries between the global and the local regions. This GL approach allows to (1) select the most appropriate guided-wave mode/frequency combinations for a given test, and (2) identify & quantify the damage that is being detected from the damage-specific reflection and/or transmission wave spectra that are obtained by the analysis. 

Selected Publications:

Spada, A., Capriotti, M. and Lanza di Scalea, F., “A Global-Local Model to Calculate the Interaction of Guided Waves with Geometrical Discontinuities and Defects in Multilayered Anisotropic Plates” International Journal of Solids and Structures, in press, 2019.

Srivastava, A. and Lanza di Scalea, F., “Quantitative Structural Health Monitoring by Ultrasonic Guided Waves,” ASCE Journal of Engineering Mechanics, 136(8), pp. 937-944, 2010.

Srivastava, A. and Lanza di Scalea, F., “Quantitative Structural Health Monitoring by Ultrasonic Guided Waves,” International Journal of Condition Monitoring and Diagnostic Engineering Management (COMADEM), Special Issue on Structural Health Monitoring, 13(1), pp. 26-33, 2010.