Effect of Joint Density on Rockburst Proneness of the Elastic‐Brittle‐Plastic Rock Mass

Abstract

The prediction of rockburst proneness is the basis of preventing and controlling rockburst disasters in rock engineering. Based on energy theory and damage mechanics, the quantitative functional relationship between joint density and energy density was derived. Then, the theoretical results were verified by numerical simulation and uniaxial compression test, and the effect of joint density on rockburst proneness of the elastic-brittle-plastic rock mass was discussed. The results show that the relationship between the joint density and the dissipated energy index of the jointed rock mass is a logarithmic function. With the same total input energy, the higher the joint density, the more the damage dissipation energy. Even in the case of high joint density, the rock mass still has limited resistance to external failure. Under the same joint density, the strength of parallel jointed rock mass is better than that of the cross-jointed rock mass, and the parallel jointed rock mass can accumulate more elastic strain energy and has higher rockburst proneness. The joint density is closely related to the ability of the rock mass to store high strain energy. The higher the joint density is, the weaker the ability to accumulate the elastic strain energy of rock mass is and the lower the rockburst proneness is. It is helpful to predict rockburst proneness by investigating and studying the properties of geological discontinuities. The research results have some theoretical and engineering guiding significance for the prediction of rockburst proneness of the jointed rock mass.

Mechanism of Hydraulic Fracturing Cutting Hard Basic Roof to Prevent Rockburst

“…When hydraulic fracturing is used in cave mining for preconditioning, boreholes are drilled from the surface or subsurface excavations into the rock mass to create multiple transverse hydraulic fractures along each borehole. ese artificial fractures aim to improve coal body cave-ability below the hard and thick rock strata and reduce fragmentation sizes in the rock strata [17][18][19][20]22].…”

“…Due to the extra-thick and rigid rock properties of basic roof, a number of induced fracturing surfaces should be preset by water jet cutting method at the target position. In doing so, continuous basic roof rock mass will be cut off by fracture surface, and the rockburst potential of the region below the hydraulic fracturing location is reduced obviously [19,20].…”

Strength Characteristics and Failure Mechanism of Granite with Cross Cracks at Different Angles Based on DIC Method

“…Cross cracks widely exist in the actual rock mass. e laboratory study on the mechanical fracture evolution of samples with cross cracks at different angles can provide important guidance for rock mass engineering [18][19][20]. Although a large number of studies have been carried out on the mechanical properties and damage evolution of prefabricated rock samples with fractures, there are few studies on the mechanical characteristics of rock samples with fractures, and most of them are confined to the description and qualitative interpretation of experimental phenomena [21][22][23].…”

Prediction and Evaluation of Rockburst Based on Depth Neural Network

“…en, the theoretical results are verified by numerical simulation and uniaxial compression test, and the influence of joint density on rockburst tendency of elastic brittle plastic rock mass is discussed. In the work of Pan et al [4], based on energy theory and damage mechanics, the quantitative functional relationship between joint density and energy density is derived. In the work of Wang et al [5], based on the instability theory and cusp catastrophe theory, the instability conditions of pillars under asymmetric mining conditions were determined.…”