Numerical Experiment Of The Mechanical Property Of Rock Specimen With Flaws Under The Static Or Dynamic Load

Because of long geological effect and various engineering disturbed, rock contains many flaws in nature. In mining, irrigation works, power project electricity, transportation, petroleum and nuclear waste disposal etc., rock with many flaws will be an important engineering object. Whether under static load or under dynamic load, the characteristics of deformation and strength of rock with flaws are more complex than that of intact rock. Therefore, the research on the mechanical properties of rock with flaws will have important significance for engineering design and construction of the underground cavity, roadbed, side slope, etc.Considering rock heterogeneity and random distribution of flaws, the failure process of rock with flaws under the static or dynamic loads respectively are simulated by using Realistic Failure Process Analysis (RFPA) in the paper. Based on this, we study the crack propagation and the interaction of multi-crack propagation of heterogeneous materials, investigating how the flaws influence the stress-strain, peak strength, AE and failure behavior of rock. The research can be divided into the following aspects:(1) Crack initiation, propagation, coalescence and failure patterns of rock specimen with flaws are studied under the static load. Firstly, the influence of obliquity of precrack on crack propagation and failure behavior of rock specimen with a single crack or flaws is analyzed under the static load. Furthermore, the influence of geometric distribution of precrack and confining pressure on crack propagation and rock bridge coalescence and failure behavior of rock specimen with double-crack is studied under the static load.(2) Crack initiation, propagation, coalescence and failure patterns of rock specimen with flaws are studied under the dynamic load. Firstly, the influence of geometric distribution of precrack on crack propagation of rock specimen with double-crack is studied under uniaxial dynamic load or biaxial dynamic load. Moreover, the influence of ratio of biaxial dynamic load on crack propagation is studied when the geometric distribution of precrack is fixed. Furthermore, the influence of loading rate of blast load, the distance of guide hole to the free boundary and the radius of guide hole on dynamic crack propagation of rock specimen is studied.Through the research above, we found that:the intrinsic factors of rock specimen such as geometric distribution of flaws and heterogeneous of material and the external factors such as load types and load ratio have a significant influence on crack propagation and failure behavior. I hope the research achievement of this paper have some academic research value to the study of crack propagation in the rock fracture mechanics and have some application value to the design and construction of geotechnical engineering.