OPTICAL METHOD OF GENERATING SLOPE AND CURVATURE CONTOURS OF BENT PLATES

In order to determine the state of stress of a thin plate under transverse elastic bending, it is necessary to have the curvature value at each and every point of the bent plate. Most experimental methods yield deflection as the primary data which have to be differentiated twice for the stress calculations. Since numerical differentiation is an inherently inaccurate process, it should be avoided if at all possible. In this paper a method is devised whereby either the first derivative (slope) or the second derivative (curvature) of the plate deflection is obtained directly in the form of slope or curvature contour fringes, thus reducing or eliminating the necessity of numerical differentiation. Examples to both static and dynamic problems are presented. © 1979.