Numerical simulations of fault stick–slip characteristics in different temperature fields at laboratory scale

Abstract

With the increasing demand for deep engineering development, there is an urgent need to study the evolution and formation mechanisms of the stick–slip process in faults at high temperatures. Although research on fault stick–slip behaviors at room temperature and laboratory scales has yielded some findings, exploring them at high temperatures is challenging, especially when acoustic emission (AE) monitoring is involved. To address this, the research conducted numerical simulations of fault stick–slip characteristics under thermo-mechanical coupling using the discrete element method to solve the problem. This approach aimed to provide insights into fault stick–slip behaviors and AE characteristics across different temperature fields. Subsequently, the evolution of the stress–strain characteristics (the number of stick–slip cycles, slip-initiation stress, slip-initiation stress drop, and maximum stress drop), energy dissipation, and AE characteristics (energy, magnitude, failure mechanism, and b-value) in the stick–slip process were systematically analyzed. The findings of this study aim to address existing shortcomings in AE tests and simulation methods related to fault stick–slip behaviors at high temperatures.