Experimental Study on Instability Mechanism of Red Shale Roadway Under Dynamic Disturbance

To delve into the instability mechanism of the surrounding rock in red shale roadways, a bespoke device was chosen to fabricate a physical model, and a similar experiment was conducted with a blasting-induced disturbance. A meticulous examination was performed on the evolution of surface fractures and the macroscopic failure patterns of the surrounding rock in conjunction with the temperature data gathered via infrared thermal imaging. In accordance with the similarity principle, five perturbation sources were strategically positioned on either side of the roadway, at the haunches, and at a location three times the roadway diameter away from the roof, aiming to comprehensively investigate the root causes of instability under dynamic loading conditions. Simultaneously, a 30° inclined rock layer model was developed using numerical simulation techniques to contrast the alterations in stress, displacement, and other relevant aspects of the surrounding rock under both static and dynamic loads. External dynamic disturbances were then applied to probe the deformation behavior. The experimental results revealed that, subsequent to applying a dynamic load at the midpoint of the left rib of the model, the horizontal and vertical displacements of the surrounding rock augmented, whereas the displacement distribution pattern exhibited minimal alteration. Under static load conditions, the displacement of the left rib surged by 22.5%, that of the right rib climbed by 20.6%, the roof displacement expanded by 33%, and the floor displacement grew by 12.2%, with the peak acceleration at the left rib being the most prominent.