Development of Modified Arcan Fixture for biaxial loading response of fiber-reinforced composites

A Modified Arcan Fixture (MAF) was developed to study the biaxial mechanical behavior of fiber reinforced composites. The MAF was calibrated compared with standard ASTM tests for an epoxy/twill woven-ply laminate. Material properties obtained with ASTM tests are implemented in ABAQUS to find the optimal notch radius that creates the most uniform stress state in gauge area. The optimized configuration of Arcan specimen was adopted to design the entire fixture numerically in preload and load steps to avoid plastic deformation. Stress concentration factor was considered in Arcan specimen under tensile loading. Biaxial experimental data for woven-ply composite in different loading angles was obtain with the MAF. Failure modes under biaxial loading show that fibers rotated towards the principle tensile direction and failure was caused by excessive stress which reached fiber limit. The ultimate shear strength corrected by considering the fiber rotation effect are in good agreement with ASTM standard results.