
MicromechanicsUnidirectionalStrengthTransverse Compression
Transverse compressive strength refers to the strength of the lamina when subjected to compression load in a direction perpendicular to the fiber direction. Micromechanics formulas used to predict transverse compressive strength are not accurate. The value needs to be measured. At the same time, the angle of the fracture plane should be measured, so that CADEC can predict the intralaminar shear strength. The angle of the fracture plane refers to the fact that a compression failure really does not happen by crushing but rather by shear. When the lamina is subjected to compression, a plane at 90 degrees with respect to the load direction is be subjected to pure compression. But a plane at another angle, less than 90 degrees, is subjected to a combination of compression and shear. The amount of shear can be calculated using Mohr's circle of stress, or stress transformations explained in chapter 5 of the textbook. Up to a critical value, the less the angle, the greater the shear. At a critical value of the angle, the material fails. The critical value of the angle is called angle of the fracture plane. This angle is clearly visible when a specimen fails during a test; thus, it can be measured. It turns out that this angle is consistently found to be in the range 53 to 55 degrees for carbonepoxy unidirectional composites.
To access this resource please sign in or register (It's free!).
