Journal Published Online: 29 January 2016
Volume 45, Issue 2

Flexural Strength Tests of Brittle Materials: Selecting the Number of Specimens and Determining Confidence Limits for Weibull Parameters



The flexural strength of brittle materials has been found to follow the two-parameter Weibull distribution. This paper describes a simple method of estimating the Weibull modulus and characteristic strength that allows for the computation of confidence intervals that will contain the true values within a specifiable level of confidence. The sample size needed to meet the experimenter's precision requirements is determined. A sample of flexural strength data from the literature is used to illustrate all of the computations. The precision of the method is compared to that of the method of maximum likelihood. It is found to be inferior to maximum likelihood for estimating the Weibull modulus but quite comparable for estimating the scale parameter.

Author Information

McCool, J.
Penn State Great Valley School of Graduate Professional Studies, Malvern, PA, US
Pages: 7
Price: $25.00
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Stock #: JTE20150250
ISSN: 0090-3973
DOI: 10.1520/JTE20150250