arXiv:cond-mat/0206201v1 [cond-mat.mtrl-sci] 12 Jun 2002 Failure time in the fiber-bundle model with thermal noise and disorder Antonio Politi 1 , Sergio Ciliberto 2 and Riccardo Scorretti 3 1 Istituto Nazionale di Ottica Applicata Largo E. Fermi 6, 50125 Firenze Italy 2 Ecole Normale Superi´ eure de Lyon, Laboratoire de Physique CNRS UMR5672, 46 All´ ee d’Italie, 69364 Lyon, France 3 Ecole Centrale de Lyon, 69131 Ecully, France (February 1, 2008) Abstract The average time for the onset of macroscopic fractures is analytically and numer- ically investigated in the fiber-bundle model with quenched disorder and thermal noise under a constant load. We find an implicit exact expression for the failure time in the low-temperature limit that is accurately confirmed by direct simula- tions. The effect of the disorder is to lower the energy barrier. PACS:: 05.70.Ln,62.20.Mk,61.43.-j 1