An Error Analysis of Failure Prediction Techniques Derived From Fracture Mechanics

Abstract

Three principal methods of failure prediction for brittle materials are analyzed statistically. Each method depends on fracture mechanics for its predictive value; hence the variance of the failure time depends on the scatter in the fracture mechanics data and the scatter in the estimate of the initial size of the strength‐limiting crack. The variance is used to calculate confidence limits for the prediction of failure for glass and SiC. Procedures for the collection and analysis of data are discussed and the implications of the analysis for lifetime prediction are evaluated.