Fracture of Quasi-Brittle Geomaterial with a Circular Hole under Non-Uniformly Distributed Compression

The influence of hole diameter on the fracture of quasi-brittle geomaterial in the stress concentration zone under non-uniformly distributed compression has been studied theoretically and experimentally taking into account the size effect. The failure load is determined using modified nonlocal criteria derived from the average stress criterion, the point stress criterion, and the fictitious crack criterion and containing a. complex parameter that characterizes the size of the fracture process zone and takes into account not only the material structure, but also the plastic properties of the material, the geometry of the sample, and loading conditions. The calculation results are compared with experimental data.