A 'ber-bridged crack with rate-dependent bridging forces

A rate-dependent model is used to represent the bridging forces acting across a 'ber-bridged slit crack in a homogeneous anisotropic elastic material, with the potential to characterize the inelastic behavior of bridged cracks in composites. The basic equilibrium equations are presented and solved, using a series of Chebychev polynomials and a suitable approximation numerical scheme. An example of a bridged crack in an isotropic homogeneous material is examined in detail. Results show that, under a constant external load, the stress intensity factors and the energy release rate increase with time until a critical time is reached, after which all these quantities approach the corresponding values for an unbridged crack. ? 2001 Elsevier Science Ltd. All rights reserved.