Influence of microstructural features on the fracture characters of rock beams with a U-shaped notch
WANG Zhao1，2，WANG Tiehang2，WANG Haiquan1，WANG Weiqin1，SHI Guangbin1
(1. School of Resource Engineering，Xi?an University of Architecture and Technology，Xi?an，Shaanxi 710055，China；
2. School of Civil Engineering，Xi?an University of Architecture and Technology，Xi?an，Shaanxi 710055，China)
Abstract：In order to reveal the influence of microstructural features on the fracture characteristics of rock beams with a U-shaped notch，the theoretical relationships of the rock apparent fracture toughness KIN with the inherent fracture toughness KIC，the critical distance L，as well as the notch radius ? were established based on the theory of critical distance. A new approach to calculate KIC and L was proposed. Then，the discrete element method was used to built two groups of rock grain-based models，one of which is different in grain size，and another group is different in heterogeneity. Both of them were employed to conduct three-points bending simulation test to obtain the fracture mechanical parameters of KIN，KIC and L. Furthermore，the influences of the grain size and heterogeneity of rock on KIC and L were studied. The results show that，the obtained KIC and L from numerical tests have a good agreement with the values calculated by the theoretical equation，which indicates that the numerical experiment is highly reliable. The microstructural features have a significant influence on the rock fracture characteristics. With the increase of grain size，the rock fracture toughness KIC gradually decrease，while the critical distance L gradually increase. Additionally，KIC and L are both decreased with the increasing of rock heterogeneity.
汪 朝1，2，王铁行2，王海泉1，王威钦1，石广斌1. 细观组构特征对含U型切槽岩石梁断裂特性的影响规律[J]. 岩石力学与工程学报, 2023, 42(9): 2175-2189.
WANG Zhao1，2，WANG Tiehang2，WANG Haiquan1，WANG Weiqin1，SHI Guangbin1. Influence of microstructural features on the fracture characters of rock beams with a U-shaped notch. , 2023, 42(9): 2175-2189.
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2023, Vol. 42 
