A photoelastic element for piezooptic strain gauges

Photoelastic and mechanical properties of a novel photoelastic element for piezooptic transducers used to measure the deformation (stress) are studied. The photoelastic element is fabricated from a plate of fused quartz and has the shape of a cross with the side surfaces having a constant and/or variable radius of curvature. The results of numerical modeling of the elastic stress in the bulk of the photoelastic element under operating loads show that its shape produces (at equal operating forces) a higher stress concentration in the relevant region of the photoelastic element than rectangular or circular shapes. The results of numerical modeling of the structural performance of this photoelastic element allow one to determine the optimum balance between the increase in the photoelastic element efficiency and the variation of the damage threshold that results from altering the shape of the element.