With the prominent economic progress and construction demand, exploitation and utilization of deep underground space are becoming more and more important. A lot of underground projects, such as deep petroleum caverns, deep drainage tunnels, deep mines and deep powerhouses have been built or programmed. Deep geotechnical engineering is in a special environment with high stress and complex thermo-hydro-mechanical-chemical (THMC) conditions. Therefore, geotechnical disasters have occurred heavily in recent years during deep rock engineering practice, such as rockburst, permeation/stress-induced collapse or large deformation, mining-induced earthquake, water inrush, and fault slip. They have seriously endangered the safety of underground geotechnical engineering and the utilization of deep underground space.

In order to mitigate the risk in deep engineering under the complicated multi-field coupling conditions, the mechanisms of rockmass rupture, deformation, failure, fluid movement, and instability in deep rockmass engineering have to be understood urgently. New theories, methods and techniques related to multi-field coupling models, numerical simulation methods, test methods, monitoring technologies, and early warning and control technologies for disaster will be extremely helpful for the construction safety of deep rock engineering.

The aim of this Special Issue is to attract original research and review articles with a focus on the new theories, methods and techniques of multi-field coupling and safety in deep rock engineering. Articles on multi-field coupling theory and simulation methods for the safety of deep rockmass engineering are especially welcomed.

Potential topics include but are not limited to the following:

• Fluid mechanics and multi-field coupling effects in deep rock engineering
• Multi-field coupling theory and simulation methods for geomaterials
• Complex mechanical behavior of deep rocks
• Temporal and spatial coupling mechanical performance of hard rock and deep rock engineering
• Cracking, deformation and failure mechanism of hard rock and deep engineering
• Risk warning, mitigation and emergency management method and technology in deep engineering
• Lessons related to geotechnical disaster in deep engineering