Abstract
This contribution focuses on the theoretical development of the method of caustics and its applicability to anisotropic materials. The method displays its full power when employed in conjunction with interactive numerical data reduction and evaluation procedures. For the analysis the selection of data points along the experimentally recorded caustic curve is done automatically, the selected points are marked on the screen and if necessary interactive correction of the positions is possible. Final proof of the correctness of the result of the automatic data point selection is achieved by comparing for acceptable coincidence the numerically generated caustic determined on the basis of the results of the data-reduction technique with the experimentally recorded caustic.
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Abbreviations
- f(x, y) :
-
deformed surface
- \(\vec \nabla f(x, y)\) :
-
gradient of the deformed surface
- S(x, y, z) :
-
wave front
- Δs(x, y) :
-
change of optical path length
- x, y, z :
-
coordinates
- \(\vec X, \vec x\) :
-
vectorial representation of points at the screen plane, model plane
- Re(...),Im(...):
-
real, imaginary part of a complex variable
- \(\gamma _{xy} , \gamma _{yz} , \gamma _{zx}\) :
-
shearing-strain components
- \(\varepsilon _x , \varepsilon _y , \varepsilon _z\) :
-
normal-strain components
- μ:
-
mixed-mode ratio
- \(\sigma _x , \sigma _y , \sigma _z\) :
-
normal-stress components
- \(\tau _{xy} , \tau _{yz} , \tau _{zx}\) :
-
shearing-stress components
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Rossmanith, H.P., Knasmillner, R.E. & Semenski, D. Crack-tip caustics in mechanically anisotropic materials. Experimental Mechanics 35, 31–35 (1995). https://doi.org/10.1007/BF02325831
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DOI: https://doi.org/10.1007/BF02325831