Brands
Vishay Measurements Group
Interactive Guide
Tech Notes
TN-509
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Errors Due to Transverse Sensitivity in Strain GagesAppendixThe following relationships can be used to correct for transverse sensitivity of the grids in any tee , delta , or rectangular rosette . The value of
does not need to be the same in each grid.
In each case,
is the Poisson's ratio of the material on
which the
manufacturer's
gage factor
was measured (usually 0.285). |
Two-Element Tee (90-degree)
Rosettes & Shear Patterns
Eq. (509.20)
Eq. (509.21)
By first applying these corrections to the indicated strains, the actual shear strain can also be calculated from the actual normal strains: 
Eq. (509.21a)
where:
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= indicated strains from gages (1) and (2),
uncorrected for transverse sensitivity.
= transverse sensitivities of gages (1) and (2).
= actual strains along gage axes (1) and (2).
= actual shear strain between gage axes (1) and
(2).
Three-Element Rectangular
(45-degree) Rosettes
Eq. (509.22)
Eq. (509.23)
Eq. (509.24)
where:
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= indicated strains from gages (1), (2) and (3),
uncorrected for transverse sensitivity.
= transverse sensitivities of gages (1), (2) and
(3).
= actual strains along gage axes (1), (2) and
(3).
Three-Element Delta (60-degree)
Rosettes
Eq. (509.28)
Eq. (509.29)
Eq. (509.30)
where:
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Appendix