Numerical Analysis Of Dynamic And Static Stress And Stress Intensity Factors For Disc Specimens Under Diametric Compression

Disc specimens have great application in testing the mechanic properties of rock, such as the cracked chevron notched Brazilian disk(CCNBD) and the cracked straight-through Brazilian disc(CSTBD) used in testing rock fracture toughness, the Brazilian disc and the flatted Brazilian disc(FBD) used in testing rock tensile strength. Numerical results of the stress and the stress intensity factor to the specimen are crucial for testing procedures.A comprehensive finite element method study is conducted on the novel specimen used for dynamic fracture-initiation toughness testing- CSTBD, to know the effects of the load types and the material properties to the dynamic stress intensity factor. Both two-dimensional and three-dimensional analysis is performed to prove the feasibility and the precision of the superposition integral method used in calculating the stress intensity factor. We suggest that the superposition integral method be used in dealing with the data of testing.On the base of the analysis of the static FBD under diametric compression, numerical analysis and compare are performed on the dynamic stress field of the Brazilian disk and FBD used in the testing tensile strength under SHPB.Using the modal taking into effects of the notch width., this paper also compute the stress intensity factor of CCNBD suggest by ISRM for rock fracture toughness test. And some conclusions have been made in this research.