Fracture mechanical behaviors and acoustic emission characteristics of Beishan granite under CCNBD test
LIU Liang1，DU Guangyin1，LI Erbing2，GUO Qian1，XIA Han1
(1. Institute of Geotechnical Engineering，Southeast University，Nanjing，Jiangsu 210096，China；
2. National Defense Engineering College，PLA Army Engineering University，Nanjing，Jiangsu 210007，China)
Abstract：To investigate the fracture mechanical behaviours and acoustic emission characteristics of Beishan granites，the MTS815 Flex Test GT rock mechanics testing system and acoustic emission(AE) three-dimensional positioning monitoring system are used to conduct Cracked Chevron Notched Brazilian Disc CCNBD tests with two different loading modes(static loading and cyclic loading). Experimental results show that mean value of KIC under static loading is 1.180 MPa?m1/2，while mean value of KIC under cyclic loading is 1.153 MPa?m1/2，which is reduced by 2.3%. The existence of subcritical crack growth is verified by cyclic loading test，and it is turned out that the failure mode of CCNBD specimens under cyclic loading do not change，the specimens are still brittle. Based on the mechanical characteristic curves and acoustic emission characteristics，the fracture propagation process and fracture characteristics of CCNBD specimens under static and cyclic loading are studied.
2020, Vol. 39 
