Paper number 385

DAMAGE-FRACTURE TRANSITIONS AS NONLINEAR PROBLEM OF DEFECTS SOLUTION

O.B. Naimark^*, V.A. Barannikov, S.V. Uvarov, D.N. Naldaev

Institute of Continuous Media Mechanics
Ural Department of Russian Academy of Sciences
1 Ak. Korolev Street, 614061 Perm, Russia;
*invited Professor at LAMEF-ENSAM

Summary

A theoretical and experimental study of crack propagation dynamics in PMMA is presented. The transition from a steady-state regime to a branching one and the stochastic scenario of crack propagation are investigated experimentally by considering fracture surface patterns and by high speed camera recording. We find that the mechanism for the change of the crack propagation regime is linked with the nonlinear dynamics of the microcracks ensemble at the crack tip and the formation of daughter cracks.

Keywords

damage, crack, structures, localization.