Elastic–plastic criterion solution of deep roadway surrounding rock based on intermediate principal stress and Drucker–Prager criterion

Abstract

Excavation‐induced rock failure and deformation near an underground opening boundary is closely associated with the intermediate principal stress, strain softening and rock mass dilation. By combining theoretical analysis and numerical simulation to explore the mechanical evolution of the roadway surrounding rock during excavation. The elastic–plastic criterion solutions for surrounding rock stress, displacement, and the plastic zone of a circular roadway were deduced by including the intermediate principal stress, strain softening and rock mass dilation, based on the Drucker–Prager criterion and the nonassociated flow rule. Furthermore, ABAQUS finite element software was utilized for numerical simulations to scrutinize the influence of mechanical parameters on stress redistribution, surface displacement, and plastic range. The results of the numerical simulations verify the reliability of the theoretical analysis and affirm the high consistency of the results with the theoretical solution. The research findings indicate that the strength of surrounding rock is significantly influenced by the intermediate principal stress, and the deformation and failure of rock mass are primarily impacted by rock mass dilation, while strain softening mainly affects the thickness of the fractured zone. Moreover, the study reveals that enhancing the residual strength of the surrounding rock can improve its resistance to deformation and failure. Furthermore, the excavation of the roadway is observed to increase the original rock stress in the surrounding rock, but increasing the ground support strength effectively controls the deformation and failure of surrounding rock. Ultimately, the research outcomes offer valuable references for engineering calculations and ground support design of surrounding rock in deep roadways.

Classification of Microseismic Signals Using Machine Learning

“…However, underground excavation activities disrupt the natural stress equilibrium of the surrounding rock mass. The excavation process generates voids that release stored strain energy within the rock mass, resulting in rock mass failure and dynamic events such as ground pressure bursts and sudden inflows of water, contributing to mining-induced dynamic disasters [1,2]. Mining-induced dynamic disasters possess significant destructive power and high levels of hazard.…”

“…Accurately identifying the source rock types of microseismic signals can help determine which rock strata or ore bodies have stress concentration or crack expansion. Additionally, long-term monitoring and data accumulation contribute to the establishment of a coal mine dynamic-disaster risk assessment model and provide a comprehensive understanding of coal mine geological structure and stress distribution.Despite T_Net demonstrating good performance in identifying the source rock of AE signals, it has several limitations:(1) In laboratory rock mechanics tests, environmental conditions are strictly controlled, resulting in fewer environmental noise influences. However, the complex conditions in real coal mining environments introduce noise components into the collected microseismic signals, reducing the model's effectiveness in field applications.…”