In the theoretical part of this paper, the Tsai-Wu tensor theory is used to determine the equation for the biaxial strength envelope of a material.
One great advantage of using the Tsai-Wu theory for investigating biaxial strength envelopes is that it may be transformed to arbitrary co-ordinate axes by means of tensor transformation laws.
In the experimental part of the paper, the strengths in compression and shear are evaluated using thick-walled tubes consisting of two layers of paper glued together with a non-penetrating glue. In addition, the strength of paper under biaxial stress is determined by subjecting paper tubes to axial tension or compression combined with a radial tension caused by internal pressure.
In the final part of the paper, the application of the Tsai-Wu tensor theory to the prediction of failure of a corrugated container is discussed, as well as practical means of limiting the number of experiments necessary to establish the biaxial failure envelope of paper.