Eur. Phys. J. B 26, 141-151 (2002)
https://doi.org/10.1140/epjb/e20020075

Failure time and critical behaviour of fracture precursors in heterogeneous materials

¹ École Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon, France
² Departamento de Física, Facultad de Ciencias, Universidad de Navarra, 31080 Pamplona, Spain
³ Facoltà di Ingegneria, Università degli Studi di Firenze, via S. Marta 4, Firenze, Italy

Corresponding author: ^a sergio.ciliberto@ens-lyon.fr

Received: 31 July 2001
Revised: 17 December 2001
Published online: 15 March 2002

Abstract

The acoustic emission of fracture precursors, and the failure time of samples of heterogeneous materials (wood, fiberglass) are studied as a function of the load features and geometry. It is shown that in these materials the failure time is predicted with a good accuracy by a model of microcrack nucleation proposed by Pomeau. We find that the time interval between events (precursors) and the energy ε are power law distributed and that the exponents of these power laws depend on the load history and on the material. In contrast, the cumulated acoustic energy E presents a critical divergency near the breaking time which is . The positive exponent is independent, within error bars, on all the experimental parameters.