The increased frequency of strain bursts in deep underground excavations represents a significant threat to both workers and operating equipment. Over the recent decades, a variety of empirical, analytical and numerical methods have been proposed to identify the triggering mechanism, estimate the location of occurrence, and assess the possible consequences of these events. While these methods allow a better understanding of the phenomenon, there's still a necessity for further work to enhance the prediction and prevention of strain bursts. This paper proposes to define a new strain burst graph that considers both the intensity and susceptibility of an event's occurrence. The graph is based on time-explicit numerical modeling of a tunnel and considers energy indicators and the IMASS failure criterion. The methodology is applied to various case studies and highlights the proper method assessment. The influence of the design parameters (Young’s modulus, Uniaxial Compressive Strength, Geological Strength Index, stress ratio k, and vertical stress) on the hazard level is explored. The methodology described in this paper provides a straightforward approach to estimating strain burst hazards. Furthermore, defining the volume and magnitude of these events helps in effectively deciding the necessary support modifications. Finally, a mathematical model is developed to assess the intensity and occurrence susceptibility levels, based on the stresses and mechanical parameters.Highlights<UnorderedList Mark="Bullet"> <ItemContent> A graphical method has been proposed to assess the strain burst hazard in hard-rock deep underground excavations </ItemContent> <ItemContent> The method is based on time-explicit numerical modeling to model the release of strain and kinetic energy during the generation of a rockburst </ItemContent> <ItemContent> It considers an intensity matrix that assess the potential unstable volume and magnitude of the event and an occurrence susceptibility matrix </ItemContent> <ItemContent> These parameters allow quantitative elements to be assessed to optimize tunnel support as mesh and bolts </ItemContent> <ItemContent> Validation through various case studies has demonstrated the method's practical applicability and reliability in real-world scenarios </ItemContent> </UnorderedList>

Graphical Assessment of Strain Burst Hazard in Hard-Rock Deep Underground Excavations to Improve Support Design

期刊论文
发表日期：

2026年2月2日

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Adeline Delonca,
Cristian Segura-Bidermann,
David Ortega,
Carla Habert,
Sergio Palma

摘要

The increased frequency of strain bursts in deep underground excavations represents a significant threat to both workers and operating equipment. Over the recent decades, a variety of empirical, analytical and numerical methods have been proposed to identify the triggering mechanism, estimate the location of occurrence, and assess the possible consequences of these events. While these methods allow a better understanding of the phenomenon, there's still a necessity for further work to enhance the prediction and prevention of strain bursts. This paper proposes to define a new strain burst graph that considers both the intensity and susceptibility of an event's occurrence. The graph is based on time-explicit numerical modeling of a tunnel and considers energy indicators and the IMASS failure criterion. The methodology is applied to various case studies and highlights the proper method assessment. The influence of the design parameters (Young’s modulus, Uniaxial Compressive Strength, Geological Strength Index, stress ratio k, and vertical stress) on the hazard level is explored. The methodology described in this paper provides a straightforward approach to estimating strain burst hazards. Furthermore, defining the volume and magnitude of these events helps in effectively deciding the necessary support modifications. Finally, a mathematical model is developed to assess the intensity and occurrence susceptibility levels, based on the stresses and mechanical parameters.

Highlights

A graphical method has been proposed to assess the strain burst hazard in hard-rock deep underground excavations

The method is based on time-explicit numerical modeling to model the release of strain and kinetic energy during the generation of a rockburst

It considers an intensity matrix that assess the potential unstable volume and magnitude of the event and an occurrence susceptibility matrix

These parameters allow quantitative elements to be assessed to optimize tunnel support as mesh and bolts

Validation through various case studies has demonstrated the method's practical applicability and reliability in real-world scenarios