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Mechanics in Engineering ›› 2009, Vol. 31 ›› Issue (2): 40-45.doi: 10.6052/1000-0992-2007-382

• Application study • Previous Articles     Next Articles

MIXED MODE DYNAMIC STRESS INTENSITY FACTORS OF CRACKED STRAIGHT THROUGH FLATTENED BRAZILIAN DISC SPECIMENS

  

  • Received:2007-08-29 Revised:1900-01-01 Online:2009-04-08 Published:2009-04-08

Abstract: In order to establish a standard for the test of mixed mode dynamic fracture of rock with the cracked straight through flattened Brazilian disc (CSTFBD) specimen, we use finite element method first to check the related results in literature on the cracked straight through Brazilian disc specimen (CSTBD). The I-II mixed mode dynamic stress intensity factors (SIFs) of the two kinds of discs with different dimensionless crack lengths (i.e. the half length of the crack normalized by the radius of the specimen) are obtained to show that the differences of the dynamic SIF's time history between these two kinds of specimens are within 10{\%}, and the numerical method used in this paper is valid. Then for CSTFBD specimens, the I-II mixed ratio, the angle of crack initiation, and the loading angle for pure mode II fracture test are obtained. The results are useful for mixed mode dynamic fracture test of CSTFBD, including specimens preparation, the location and directional alignment of the strain gages, as well as the estimation for the crack initiation time and the crack initiation direction.

Key words: mixed mode dynamic fracture, cracked straight through