Comparative study of phase change theory and zonal fracturing field measurements in deep surrounding rocks

Abstract

The topic of zonal fracture in deep surrounding rock roadway under high ground stress is a challenging and widely researched area in geotechnical engineering, with significant implications for the safety of deep engineering project. When the material yield damage occurs, there is a certain dissipation of energy, and as the dissipation proceeds, the material structure also produces some corresponding changes to form a new organizational structure, the process is similar to the self-organization process on the concordance, at this time the traditional elastic-plastic mechanics is not very useful, need to use the physical theory. Deep tunnel surrounding rock under high ground stress, when its deformation exceeds the elastic limit, will also has a similar dissipation structure phenomenon. The surrounding rock structure needs to go through a self-organization process to form a new dissipative structure, and this process is similar to the phenomenon of progressive phase change in physics. This paper explores the deformation and failure process of the surrounding rock in deep roadway, which is characterized as a gradual phase transition from solid to fluid. The study analyzes various zonal fracturing phenomena in field scale, laboratory scale, and simulation tests, and develops a phase transition theoretical model to approximate the nonlinear higher order control equation using Poincare-analytic parametric regression method. The sensitivity of each parameter in the approximate solution is also analyzed. Finally, the study validates the theoretical model by comparing the calculated results with the on-site measured data of zonal fracturing in a 700 m deep horizontal roadway in a metal mine.

Keywords

• phase transition theory
• deep surrounding rock
• partition rupture
• nonlinear
• rock mechanics