Combined effect mechanism of linear loading and disturbance with different amplitudes on sandstone

The combined effects of the stress paths under linear loading and perturbation conditions were investigated via a comprehensive analysis of the experimental results integrating mechanical theory and prior research findings. The YOLOV5 and FAST feature point detection algorithms were used for three-dimensional crack reconstruction, providing insights into the fracture morphology of the experimental specimens and showing the crack propagation patterns on the specimen surfaces. The energy evolution trend was explored, revealing a notable linear trend in the cumulative values. The stiffness evolution trend under compound paths was examined, elucidating the change mechanism through integration with established laws.