A state-of-the-art review on rock seepage mechanism of water inrush disaster in coal mines

Abstract

Water inrush is one of the most dangerous disasters in coal mining. Due to the large-scale mining and complicated hydrogeological conditions, thousands of deaths and huge economic losses have been caused by water inrush disasters in China. There are two main factors determining the occurrence of water inrush: water source and water-conducting pathway. Research on the formation mechanism of the water-conducting pathway is the main direction to prevent and control the water inrush, and the seepage mechanism of rock mass during the formation of the water-conducting pathway is the key for the research on the water inrush mechanism. This paper provides a state-of-the-art review of seepage mechanisms during water inrush from three aspects, i.e., mechanisms of stress-seepage coupling, flow regime transformation and rock erosion. Through numerical methods and experimental analysis, the evolution law of stress and seepage fields in the process of water inrush is fully studied; the fluid movement characteristics under different flow regimes are clearly summarized; the law of particle initiation and migration in the process of water inrush is explored, and the effect of rock erosion on hydraulic and mechanical properties of the rock media is also studied. Finally, some limitations of current research are analyzed, and the suggestions for future research on water inrush are proposed in this review.

Research on the Safety Thickness of Tunnel Outburst Prevention in Water-Rich Fault Fracture Zone Based on Janssen’s Theory

“…(1) The same basic assumptions as Janssen's silo theory (2) The cohesion strength between the rock mass in the fault zone and the fault plane is not considered, that is, the frictional P f between the rock mass in the fault zone and the fault plane is the product of the horizontal in situ stress P xy in the fault fractured zone and the friction coefficient μ…”

“…At the same time, the loose medium and mineral components of the fault are dissolved in the water body, and the seepage channel expands. In turn, the seepage rate of the rock mass will be increased, forming a "vicious circle," resulting in the original rock structure damage [1,2]. Especially for deep-buried tunnels, the surrounding rock is subject to higher ground stress and water pressure, and the hydraulic coupling effect is intensified, which can easily lead to engineering disasters such as water and mud inrush [3][4][5].…”

Analytical Damage Model for Predicting Coal Failure Stresses by Utilizing Acoustic Emission

“…Deep mining coal seams can result in coal and gas outbursts, rock bursts, and gas explosions due to high stress, high pressure, and high concentration of gas [2][3][4][5]. In recent years, hydraulic flushing and water injection have been widely used to alleviate coal and gas outbursts, reduce coal dust, and prevent coal seams from spontaneous combustion [6][7][8][9][10][11]. Coal seams undergo significant changes due to hydraulic measures, resulting in significant changes in their mechanical characteristics and geophysical properties as a result [12][13][14][15].…”

The Infrared Radiation Characteristics of Sandstone Fracture Seepage under Coupled Stress-Hydro Effect

“…However, the development of underground space and other geotechnical engineering is often restricted by groundwater [10][11][12][13][14][15][16][17]. Because water can cause changes in the physico-chemical properties of rocks, it is generally regarded as one of the most active and direct factors in geotechnical engineering disasters [18][19][20][21][22][23][24][25]. The rock in the engineering site is usually subject to the double action of water pressure and external force.…”