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Abstract

Two new analytical approaches are proposed for the off-axis tension test problem. Both of them are based on the Second Castigliano’s theorem. In the first one, a simple stress field that satisfies equilibrium conditions is used. In the second approach, integration constants of the stress field obtained by Pagano and Halpin are calculated directly, without the use of the displacement field. The first approach shows the points of maximum normal and shear stresses in a qualitative manner. The second approach, besides the fulfilment of equilibrium and compatibility conditions, minimizes the strain energy. Furthermore, both approaches give the same solution for bending moments and shear forces at specimen ends caused by coupling effects. After analyzing the stresses at critical points in the principal material directions, it is shown that the value of in-plane shear strength is usually underestimated. The effect of end constraints on the obtention of in-plane shear modulus is also analyzed.

Keywords

off-axis tensile test in-plane shear properties strain energy

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References

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New Considerations on the Stress Field in an Off-axis Tensile Test

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