A PHENOMENOLOGICAL STUDY OF TRIAXIALLY BRAIDED TEXTILE COMPOSITES LOADED IN TENSION

An experimental program has been conducted to define the mechanical re sponse of three two-dimensional triaxially braided textile composite m aterials to tensile loading. The materials' longitudinal and transvers e moduli, Poisson's ratios, and strengths were measured in a series of tests. In addition, the physical mechanisms that determined these res ults were defined Moire interferometry was used to define the full fie ld strain distributions on the surface of the specimens. Enhanced X-ra y radiography and surface replication techniques were used to identify the damage mechanisms exhibited in these materials. Transverse cracks and delaminations were located and their propagation with increasing load was monitored through the use of these techniques.