In order to explore the microcrack initiation, propagation and damage evolution of rock samples with different crack types (opening and closed), inclination and crack length, based on PFC2D, the fractured rock sample model was constructed and the uniaxial compression numerical tests were carried out. The initial crack and failure characteristics of rock sample under different crack obliquity and type were explained from the perspective of mesoscopics. The damage analysis of rock samples was carried out from the perspective of energy. The results are as follows. With the increase of crack inclination angle, the peak strength of the open type is positively correlated, while that of the closed type decreases first and then increases. The elastic modulus is consistent with the change of peak strength. When 30°≤α≤60°, the microcrack initiation characteristics of the two kinds of fractured rock samples are consistent. When 60°≤α≤90°, the failure paths of the two rock samples are similar. The damage variable and correction coefficient were defined based on the energy of cementation failure, and the evolution model was established. The rationality of the model was verified from the perspectives of fracture type, inclination angle and length. The research results can provide a theoretical basis for further understanding the damage evolution process of fractured rock mass after loading.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |