Rosette strain gages are designed with three active elements generally configured at 45° angles, but can be designed to customer specifications. In this configuration, three linearly independent strain measures are used to determine the three independent components of plane strain. Lead exits are offered in various formats.
Chevron strain gages are designed with two active elements oriented at right angles (90°) to each other, bonded to a single shim. Most popular for the ease and accuracy of Poisson’s Ratio measurements. (A material loaded in one direction will undergo strains perpendicular to the direction of the load as well as parallel to it. The ratio of the transverse strain to the longitudinal strain is called Poisson’s Ratio.)
Axial configured strain gages measure strain in one principal direction: along the long axis of the shim. They can be oriented in either the longitudinal or circumferential direction on the component being tested, and the shims can be pre-curved to fit surfaces with small radius curvatures.
Shear configured strain gages are used to measure the angular distortion that results when a component is subjected to torque or twisting. The shear strain gage design is more compact than the Chevron gage, facilitating its use where installation constraints are a concern.
