Determination of G(12) by means of the off-axis tension test. Part II: a self-consistent approach to the application of correction factors

Several different tests and procedures have been proposed for the determination of the intralaminar shear modulus G(12) in composite materials. The off-axis tension test, the +/-45 degrees test and the Iosipescu test are the most widely used. The advantages of the off-axis test are the ease of specimen preparation and the simplicity of the test procedure. A detailed review of the most significant papers on the determination of G(12) by means of the off-axis test has been presented in Part I of the present study. In this paper, a new graphical procedure, based on the numerical results from a test with clamped end conditions, is introduced. The use of these graphs requires the use of clamping conditions in the tests. Thus, an experimental study, using Moire interferometry, has been carried out to check the satisfaction of this condition in the most commonly used methods of performing the test. It has been found that a specimen with bonded end tabs reproduces the most reliable clamped condition. Finally, the results of several 10 degrees off-axis tests on a graphite-epoxy composite are presented as a demonstration of the applicability of the correction scheme proposed in a wide range of specimen aspect ratios. (C) 2001 Elsevier Science Ltd. All rights reserved.