A numerical study on the application of the Weibull theory to brittle materials

In this paper, the effects of assuming that a brittle material can be model led by the two-parameter Weibull distribution, if the true representation o f the material behaviour is actually a three-parameter distribution, are ex amined. It is shown that if data from a material characterisation test is u sed to predict the failure of a component and the stressed surface areas ar e very different, then this can lead to major discrepancies in the predicte d failure stress. It is also shown that if the three-parameter model is a t rue representation of the material behaviour, then the Weibull modulus for the two-parameter approximation will vary with surface area. (C) 2001 Elsev ier Science Ltd. All rights reserved.