Experimental study and modeling of single yarn pull-out behavior of kevlar® 49 fabric

Single yarn pull-out behavior of Kevlar (R) 49 fabric with varying lengths and pre-applied transverse tensile forces is studied. Results indicate that both peak pull-out force and energy needed to pull an individual yarn increase with specimen length and transverse pre-load. An analytical model is used to investigate the frictional shear properties diagram between the orthogonal warp and fill yarns. Maximum static and dynamic frictional shear strength of contact interfaces of warp and fill yarns are obtained by fitting the experimental data. The periodic nature of the post-peak behavior of pull-out response is simulated by representing the contact area as a sinusoidal function with a constant period. Finally, a three-dimensional finite element model is used to simulate the single yarn pull-out behavior and the results show that pull-out force is significantly influenced by the friction between yarns and transverse pre-load. (C) 2011 Elsevier Ltd. All rights reserved.