State Key Laboratory of Water Resource Protection and Utilization in Coal Mining
Mengdong Energy Co., Ltd.
State Key Laboratory of Coal Resource and Safe Mining, China University of Mining and Technology-Beijing
China Energy Guoyuan Electric Power Co., Ltd.

煤炭高强度开采中含水层保护是绿色安全开采的难点，采动局域渗流响应规律则是含水层保护方法与技术的认知基础。研究采用多场源耦合分析思路和有限的矿区水文观测数据，通过剖析开采行为与渗流场响应耦合关系，构建采动局域地下水系统和分析采动渗流场时−空演化规律及采动−渗流耦合累积效应，结合典型案例分析，形成适于矿区地下水保护的采动渗流场分析方法。结果表明：① 分析提出基于“开采激励−覆岩应变−渗流场响应”耦合和开采动能量与渗流场势能量传递关系的采−渗耦合机制，构建了描述采动局域渗流场状态的采动渗流系统(MSS)和采动渗流场的导通区、扰动区和辐射区划分架构；② 构建集导通区“柱状渗流模型”和扰动−辐射区“井−渗”态模型为一体的采动渗流场分析简化模型，提出采−渗耦合系数、采动渗流量、视导水系数、源−位距等采动渗流场描述参数，含水层损伤、安全开采风险等含水层保护分析参数；③ 揭示采−渗耦合系数是影响局域采动渗流响应特征的关键因子，发现硬岩类较软岩类覆岩耦合强度和影响范围大，低导水性较高导水性含水层的采动渗流场响应区域窄、频度高和累积影响距离近，采动渗流量和介质导水性等响应显现周期性、振幅波动性和涌流脉动性等特点；④ 提出基于采−渗累积效应的导通区辨识分析流程，针对采区非均匀介质的采动区域渗流异常均衡分析法和采动工作面导通区辨识的约束均衡分析法，基于非均匀含水层开采损伤控制的开采风险、覆岩厚度和采高分析方法；⑤ 应用表明：采动渗流直接影响III含和波及II含，采动期(2012—2019)累积影响半径分别超过2 km和6 km；III含采动渗流量显著低于II含，但采−渗协同响应显著，总量接近同期全区工作面矿井水实测量。其中，主要导通区在首采工作面初采段，渗流量源于III含直接“排泄”和II含大量的越层“补给”，其他采区总量稳定且水平较低，主要源于III含采动裂隙渗流及少量II含周期性沉陷裂缝越层补给；巨厚多含水层时采用“保II控III”策略和“低进、高推、慢停”柔性回采模式，西区和东区安全采高分别提升到8～12 m和16 m左右后，续采区渗流异常水平显著下降和无采动涌水现象实证目标含水层保护效果显著。

Aquifer protection in high-intensity coal mining is difficult to green and safe-mining, due to less knowledge of the response law of local seepage-flow in the mining area after aquifer damaged for the protection method and techniques. Adopting the coupling analysis idea of local multi-field source, the study focuses on the response law of mining-seepage field and aimed to revel coupling relationship between locally mining and the seepage field response and construct local mining groundwater system used to analyze the time-space evolution law of mining-seepage field and its cumulative effects, with the limited hydrological data including ground and underground observation. Based on application analysis of typical case, the analysis method of mining-seepage field is pro-posed, suitable for groundwater protection and engineering restoration in the mining area. The results show: ① Based on coupling relation of “mining excitation-overburden strain-seepage field response” and the energy transfer relationship from mining kinetic and seepage potential energy, the mining-seepage coupling mechanism is proposed. The mining seepage system (MSS) is constructed for describing the state of the operative local seepage field being divided into conduction zone, disturbance zone and radiation zone; ② The simplified mining-seepage effect models are established, including the “columnar seepage model” of the conduction zone and the “well-seepage” state model of the disturbance-radiation zone. Relative analyzing parameters are proposed, such as the miming-seepage coupling coefficient, the mining-seepage flow, the apparent water conductivity, distance of source-measuring point for describing statues of mining-seepage field, and aquifer damage, the risk of water-reserving safe-mining and mining height used for the groundwater protection analysis; ③ Revealed that the mining-seepage coupling coefficient is the key factor affecting the characteristics of the local mining-seepage response, featured that the hard rock overburden is larger than soft rock in coupling strength and influence range, and that the low-conductivity aquifer is narrower than high-conductivity in mining seepage field response area, higher in the response frequency and closer in the cumulative influence distance. Timing variation of mining-seepage flow and the water conductivity are characteristics of the periodicity, amplitude fluctuation and in-rush-flow pulsation of the reactive response; ④ Based on mining-seepage coupling cumulative effect, the identification process of the conduction area is proposed, containing the equilibrium analyzing method for“suppling, run-off, excretion”of mining area and the constraint-equilibrium method for induced-seepage flow of the mining face. Analysis method of overburden thickness, mining risk and mining height proposed, aimed to control mining damage of heterogeneous aquifer; ⑤ The application indicates that the mining-seepage disturbs directly the III aquifer and affects the II aquifer, and the cumulative impact range exceeds respectively 2 km and 6 km, during mining period (2012–2019); that III’ mining-seepage flow is significantly lower than that of II aquifer with obvious synergistic response of mining-seepage, its total amount of the flow close to the actual mine water in the same period; that the initial section W01 mining face is the main conducting zone, with mining-seepage flow sourced from direct“excretion” of III aquifer and indirect supply of II aquifer; that total amount of other mining areas was stable in low-level, mainly from the seepage of III aquifer mining seepage and a small part from the cross-layer replenishment of II aquifer due to periodic subsidence fractures; that strategy of “Protecting II aquifer by Controlling III” and the flexible recovery mode are adopted in the case of large and thick multi-aquifers, in which safe mining height in the western and eastern areas was increased to about 8−12 m and 16 m, respectively, lead to obvious effect on the aquifers protection confirmed by the significantly decreased abnormal level of seepage in the continuation mining area and the phenomenon of no water inrush.

国家重点研发计划资助项目(2016YFC0501100)；国家自然科学基金青年基金资助项目(52004011, 52004012)

张建民，李全生，曹志国，等. 采动渗流场分析方法[J]. 煤炭学报，2023，48(10)：3628−3645.

ZHANG Jianmin，LI Quansheng，CAO Zhiguo，et al. Analysis method of mining seepage field[J]. Journal of China Coal Society，2023，48(10)：3628−3645.