Experimental Mechanics

, Volume 7, Issue 4, pp 168–175 | Cite as

Moiré study of anticlastic deformations of strips with tapered edges

Principal objective of paper is to verify the theoretical deformations for optimally tapered strips by experiments using the moiré method
  • W. E. Nickola
  • H. D. Conway
  • K. A. Farnham


When a thin elastic strip is bent, anticlastic deforming of the cross section takes place, and the edges move away from the center of curvature. This effect can have serious consequences in several applications. However, it has been found that the magnitudes of the deformations can be very greatly reduced if the concave edges of the bent strip are tapered.

The proportions of the tapers have already been worked out theoretically so as to optimize the reduction in anticlastic deformation in any given strip bent to a known radius of curvature. The main purpose of the present paper is to verify the theoretical deformations for optimally tapered strips by experiments using the moiré method.


Mechanical Engineer Fluid Dynamics Elastic Strip Tapered Edge Concave Edge 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



half-width of strip (Fig. 8)


half-width of uniform portion of strip (Fig. 8)


dimension defined in Fig. 8


radial pressure


width ratiob1width ratio/b


thickness ratiot1/t0


thickness of uniform portion of strip (Fig. 8)


thickness defined in Fig. 8


thickness defined in Fig. 8

x, y

Cartesian coordinates


final deviation of middle surface fromx−y plane


initial deviation of middle surface fromx−y plane


flexural rigidity=Et03/12 (1 −μ2)


Young's modulus


distance between strain-gage grids


bending moment per unit width


shearing force per unit width


longitudinal radius of curvature


maximum lateral relative displacement of concave surface of strip [eq (2)]



b(Rt0)−1/2 [3(1 −μ2)]1/4


b(Rt2)−1/2 [3(1 −μ2)]1/4


Poisson's ratio (0.35 for Plexiglas)


2 (1 −y/b2)1/2


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Copyright information

© Society for Experimental Mechanics, Inc. 1967

Authors and Affiliations

  • W. E. Nickola
    • 1
  • H. D. Conway
    • 1
    • 2
  • K. A. Farnham
    • 1
  1. 1.Systems Development DivisionIBM Corp.Endicott
  2. 2.Dept. of Theor. & Applied MechanicsCornell UniversityIthaca

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