Extended MTSN criterion for fracture analysis of soda lime glass

This paper investigates brittle fracture in soda lime glass subjected to mixed mode I/II loading using different fracture criteria. Different sets of mixed mode I/II fracture test data from literature, conducted by cracked Brazilian disk specimen, are utilized to study brittle fracture in soda lime glass. The fracture initiation conditions in soda lime glass is examined by different traditional fracture criteria including Strain Energy Density, Maximum Tangential Stress, and Maximum Tangential Strain criteria. It is shown that the traditional criteria, which only consider singular stress (strain) terms, are not able to properly predict the fracture test data. The test data are then predicted by an extended version of the maximum tangential strain (EMTSN) criterion which takes into account the effect of first nonsingular strain term as well as the singular strain terms. It is found that the mixed mode fracture toughness of the soda lime glass as well as the crack initiation direction can be predicted successfully by the EMTSN criterion.