This study analyzes the ability of coal mine underground reservoirs to protect groundwater resources. As the demand for coal mining continues to increase, the potential impact on groundwater resources around mines has become a growing problem. Underground water reservoirs, also known as coal mine underground reservoirs, have been constructed as a solution to protect water wastage in mining operations. However, there is a lack of awareness related to the ability of underground water reservoirs in mines to protect groundwater resources. In this study, we used FLAC^3D software to analyze the formation process, water storage volume, and central storage location of the underground water reservoir in Zhangshuanglou Coal Mine. The results show that the damaged volume is 3.39 × 10⁶ m³, and the groundwater resources that can be protected by coal mine underground reservoirs in the study area amount to 1.98 × 10⁵ m³. We found that the storage capacity of underground reservoirs is more significantly affected by the extent of mining, which can be expressed as y = 49,056.44 + 255.75x + 1.46x² (R² = 0.995) (x ≠ 0). Additionally, the water storage location obtained through simulation can provide a reference for the construction of underground reservoir regulation and water storage projects. The results of the water quality analysis indicate that the concentrations of SO₄²⁻ decreased by 42% with the closure of the mining area, and the pH also gradually converged to neutral. This highlights the significant role of underground water reservoirs in coal mines in promoting green production and protecting water resources and the environment.

The Tarim Basin in Xinjiang is located in the northwest inland arid region of China, but research shows that the region is rich in groundwater resources. To understand the hydrochemical characteristics and water quality of shallow groundwater in the desert area of the southern margin of the Tarim Basin, the groundwater was systematically sampled and tested. The ion characteristics and evolution mechanism of groundwater were analyzed by mathematical statistics, Schukarev classification, Piper three-line diagram, Gibbs model and ion ratio. Water quality was evaluated by the water quality index method (WQI) and irrigation water suitability-related parameters. The results indicated that the dominant cation in the study area is Na⁺, and the main dominant anions are SO₄²⁻ and Cl⁻. According to total dissolved solids (TDS), the groundwater mainly belongs to brackish water and semi-saline water. The hydrochemical chemistry types are mainly Cl·SO₄-Na·Mg type, followed by Cl-Na type, and the ion source is mainly the weathering and dissolution of evaporation rock, silicate and sulphate. The hydrochemical process is primarily controlled by evaporation concentration and rock weathering, and the cation exchange is weak. Furthermore, the WQI spatial distribution map shows that the groundwater in the middle of the study area is unsuitable for drinking and there are two areas with high WQI values greater than 500. In contrast, the good-excellent groundwater is scattered in the East. The groundwater generally has high to very high salinity, with significant changes in alkalinity. In addition, 54% of the water samples exceed the magnesium hazard (MH) limit. Therefore, certain measures should be taken before irrigation. This study has important implications for the rational development and reasonable utilization of local groundwater.

Undrained shear strength serves as one of the crucial indicators for analyzing the strength and assessing the stability of clay. To enhance the predictive capability of undrained shear strength, we introduced a hybrid stacking model, the KSMRX, which leverages the Bayesian optimization algorithm. Comparative analyses against base models revealed that the KSMRX model significantly enhanced prediction accuracy, elevating it from 51.3% to 72.5%. This substantial improvement underscored the efficacy of our approach in predicting drained shear strength. Moreover, when compared with the prediction accuracies of 15 other hybrid models, the KSMRX hybrid stacking model consistently demonstrated superior performance. Therefore, this study not only presents a novel and more convenient computational approach, facilitating the acquisition of highly accurate geotechnical parameters, but also serves as a reference for the implementation of geotechnical engineering projects.

In order to predict the ground settlement in a scientific, intuitive, and simple way, based on the theory of Bio-consolidation, a three-dimensional fluid-solid coupled numerical calculation programme FGS-3D for ground settlement was compiled by using the Fortran 95 language, and a front-end operation platform was developed by using Microsoft VisualBasic, so that a three-dimensional variable-parameter fully coupled viscoelastic-plastic model of ground settlement was constructed using the city of Yancheng as an example, and the development of ground settlement and horizontal displacement changes from 2021 to 2030 were predicted. The results show that the three-dimensional fully coupled finite-element numerical model of building load, groundwater seepage, and soil deformation established by the above computer development program can directly create a hydrogeological conceptual model of groundwater mining and predict ground settlement, so as to achieve the visualisation of the three-dimensional seepage of groundwater and the fully coupled simulation of ground subsidence in the whole process of groundwater mining. Under the joint action of construction load and groundwater mining, the water level of the aquifer in Yancheng City rises by 1.26 m on average in the main groundwater mining area of the group III pressurised aquifer, forming two smaller landing funnels, and the lowest water level of the two landing funnels is −15 m.

The development of a water-conducting fracture zone is a critical factor in understanding and predicting water inrush from coal mine roofs, as these zones facilitate the inflow of water from overlying aquifers. However, traditional methods such as empirical formulas and drilling, as well as single physical investigations (such as transient electromagnetic), can only estimate the height of these fault zones and often cannot accurately obtain precursor information of roof water inrush during the mining process. In this study, a comprehensive evaluation of the 13,101 working face of the Shengfu Coal Mine in Shaanxi, China, is being carried out using microseismic monitoring and parallel electrical methods. On the basis of the microseismic results, the height of the water-conducting fracture zone is obtained to be 57 m. The average variation of the natural potential of the coal seam roof was obtained by the parallel electric method, which was all less than 250 mV, with no obvious anomalous seepage electric field and no large centralized water-conducting channels found. However, the decrease in resistivity and natural potential indicates the precursor information of water seepage when the fracture zone develops to 40–50 m. This approach aims to monitor the development of water-conducting fracture zones by combining microseismic monitoring with parallel electrical methods while simultaneously capturing changes in roof seepage. This will enhance safety and facilitate more informed decision-making in complex hydrogeological environments.