The Determination of Elastic Modulus of Rock Materials With the Cracked Straight Through Brazilian Disc Specimen by the Compliance Method

摘要

Based on the compliance method of linear elastic fracture (LEFM) theory, a method to determine the tensile Elastic modulus by measurement of the elastic compliance of cracked straight through Brazilian disc specimen (CSTBD) is established. This method uses the elastic compliance calibration of fracture toughness test specimen geometry, the dimensionless elastic compliance E' CB only related to the specimen geometry is calabrated by using three dimensional isoparametric boundary element method (3D-BEM), herein B is the known specimen width, the tensile Elastic modulus E' is obtained by measurement of the specimen elastic compliance C_s. Specimen elastic compliance is measured with two sized CSTBD specimens of gray rock which is taken from Sichuan province. The testing results show that the tensile Elastic modulus evaluated by this proposed method coincides satisfactorily with the elastic modulus determined from the standard uniaxial tension tests following ASTM and the method are found to have little specimen size effect. Such a testing procedure is a simple, convenient and easy to set up.