Research on Arch Model and Numerical Simulation of Critical Water and Sand Inrush in Coal Mine near Unconsolidated Layers

Abstract

With the continuous increase of the upper limit of coal mining, in mining areas near unconsolidated layers, water and sand inrush disasters occur from time to time, seriously threatening the safety of mine production. In this paper, the process of water and sand inrush accidents induced by mining near unconsolidated layers is analyzed using mechanical analysis and numerical simulation methods, based on the principle of silo unloading and arching and combined with actual water and sand inrush characteristics; the critical water and sand inrush arching mechanism is explained. The paper also proposed and established three critical arching mechanics models (interlocking arch, bonded arch, and transition arch), deduced the mathematical expression of interlocking arch and transition arch, and obtained the critical instability conditions of the arch and its influencing factors. The research results have guiding significance for the occurrence of water and sand inrush disasters and the judgment of the degree of damage in mining near unconsolidated layers.

Review and Challenges in the Geophysical Mapping of Coal Mine Water Structure

“…Faults can be divided into tensile faults and compressional faults based on their mechanical properties, and different mechanical properties and structural lithology result in the waterconducting capabilities also differing (Figure 2(a)) [39]. For extensional faults, the majority of the fracture surfaces will be open and contain obvious gaps, the fracture belts tend to be filled with breccia, and such loose and porous zones are known to be beneficial to the flow and storage of groundwater [40,41]. Therefore, tensile faults are good channels for water-conducting and water-flowing actions within coal mines.…”

A Multifactor Quantitative Assessment Model for Safe Mining after Roof Drainage in the Liangshuijing Coal Mine

“…However, the experimental conditions are way different from the actual conditions in the mine, which makes the results less convincing. 15 − 17 What is more, the geological conditions, hydrogeological conditions, lithology, and mining conditions are different from one mining area to another mining area, the research results cannot be widely applied, and the existing conclusions are not suitable for the Liangshuijing coal mine. Therefore, the formation of the water damage from the roof is still unclear, leading to a lack of effective prediction and prevention technology.…”

Archives of Mining Sciences

“…The breaking crack area is the main channel feeding in groundwater which caused small particle migration from fractured rocks of the faults, and to investigate particle migration with water flow, a 3D model was established for solid-water two-phase flow [19]. Comprehensive use of multiple analytical methods based on the principle of silo unloading and arching, combining them with actual inrush features to analyse the process of water and sand inrush accidents [20]. A callable model for inquiring about the mechanical intensity of the retaining wall was set up and improved safety management of water and sand flooding disasters on roadways [21].…”