Numerical Solutions of Second Elastic-Plastic Fracture Mechanics Parameter in Test Specimens under Biaxial Loading

摘要

Extensive finite elements analyses have been conducted to obtain solutions of constraint parameter A,which is the second parameter in a three-term elastic-plastic asymptotic expansion for crack-tip field,for test specimens under biaxial loading.Three mode I plane-strain test specimens,i.e.single edge cracked plate (SECP),centre cracked plate (CCP) and double edge cracked plate (DECP) were studied.The crack geometries analysed include shallow to deep cracks,and the biaxial loading ratios analysed are 0.5 and 1.0.Solutions of parameter A were obtained for materials following the Ramberg-Osgood power law with hardening exponents of n=3,4,5,7 and 10.Remote tension loading were applied which covers deformation range from small-scale to large-scale yielding.Based on the finite element results of constraint parameter A,crack-tip constraint effect for cracked specimens under biaxial loading is analysed.Using the relationships between A and other two commonly-used second fracture parameters,Q and A2,the present solutions for A can be used to calculate parameters Q and A2.