# A Comprehensive Review of Mechanisms, Predictive Techniques, and Control Strategies of Rockburst
## 2 Rockburst Definition and Classification
### Classification of Rockbursts
[PERSON] [38] classified rockbursts into five types based on the amount of time from unloading to occurrence: instant rockburst, standard rockburst, delayed rockburst, strainburst, and impact-induced rockburst, [PERSON] [54] divided rockbursts into two major types based on stress routes and experimental procedures: strainbursts and impact-induced bursts. Based on in-situ observations of rockburst at the Jinping II hydropower facility, [PERSON] [55] classified rockbursts into two types based on observations at the Jinping II hydropower facility: immediate rockburst and time-delayed rockburst. [PERSON] [56] and [PERSON] [57] classified rockbursts into two or three groups based on the control factors of surrounding rock collapse and stress release mode. [PERSON] [58] classified rockbursts into six primary geomechanical types based on geomechanical assessments in China. These classifications are summarized in Table 3. \begin{table}
\begin{tabular}{l l l l} \hline \hline
**Seismic Event** & **Postulated Source Mechanism** & **First Motion from Seismic Record** & **Richter Magnitude, M** \\ \hline Strain-bursting & \begin{tabular}{l} Spalling rockburst with severe \\ ejection of fragments \\ \end{tabular} & Usually undetected, could be implosive & \(-\)0.2–0 \\ \hline Buckling & \begin{tabular}{l} Outward expulsion of pre-existing \\ larger slabs parallel to the opening \\ \end{tabular} & Implosive & 0–1.5 \\ \hline Face crush & \begin{tabular}{l} Violent expulsion of rock from the \\ tunnel face \\ \end{tabular} & Implosive & 1.0–2.5 \\ \hline Shear failure & \
\begin{tabular}{l} Violent propagation of shear fracture \\ through the intact rock mass \\ \end{tabular} & Double-couple shear & 2.0–3.5 \\ \hline Fault-slip &
\begin{tabular}{l} Severe renewed movement on \\ existing fault \\ \end{tabular} & Double-couple shear & 2.5–5.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Classification of rockbursts [17]. Figure 1: Types of rockburst damage mechanisms and damage severity (modified from ref. [7]). [PERSON] [59] classified rockbursts into three types based on the magnitude of the dynamic stimulation force: inherent rockburst, triggered rockburst, and induced rockburst. This categorization is commonly used by mining and geotechnical professionals to understand how rockbursts occur. However, different categorization systems may provide contradictory findings due to varying assessment indexes. [PERSON] [58] provided one of the most comprehensive rockburst classifications, characterizing six types based on the failure plane, cracking (tensile or shear), and energy released. The best categorization for a mining site may be obtained by combining this classification with field observations and recorded seismic data. Rockburst predictions can be divided into short-term and long-term predictions, with short-term predictions based on field monitoring and long-term predictions based on the potential for rockbursts and field circumstances. However, rockburst evaluation and classification also depend on engineers' appraisals and the availability of data, and a comparable occurrence may result in different measurements depending on who made the classification. Future studies should strive for a unified rockburst categorization technique.