Font Size: 

A simple probabilistic model of fatigue crack growth, caused by deterministic loads, denoted as VFT, has been here developed: this approach allows to obtain the probability of samples breakage as a function of time by a direct analisys of virtual generated data. VFT model has been compared with two classical approaches found in literature: the first, developed by Spencer, Enneking and Tang (1990), is based on the randomization of a semiempirical fatigue law by a gaussian white noise: the probability of sample breakage is thus obtained in the frame of Itô equations and Markovian diffusion theories. The second model, developed by Ray and Tangirala (1997), is hinged on a discrete time representation of the autocorrelation function of fatigue crack lenght. Comparision with fatigue tests has been performed on CT samples made by Titanium b Alloy Ti-15V-3Al-3Cr-3Sn.