Combining this equation with equation 2.5, gives (2.7)
from which it can be seen that the ratio of the maximum shear stress to the maximum tensile stress depends on s and D, i.e., specimen geometry. A short likelihood a thick specimen increase the ratio and therefore enhances an aligned of a shear failure. It follows that a short, thick specimen of fibre composite with the fibres parallel to the length of the specimen (Figure 2.24(e) will fail by shear at the fibre-matrix interface provided This where orc tensile strength of the composite, is less than D/2S test configuration is known as a short-beam bend test or the inter r shear strength (ILSS) test.