侏罗系煤层上覆N2红土采动破坏突水机理及防控研究

The Laterite of Neogene pliocene series (N2) over Jurassic coal layers distributed regionally in Northwest China, abbreviated as N2 Laterite, is of special natures. N2 Laterite is the key aquifuge soils for protecting the shallow water from being destroyed by coal mining. The bigger the development of coal mining is, N2 Laterite are destroyed more seriously, causing more frequent inrush accidents of the shallow water and growing ecological environmental disasters in this arid and semiarid areas. It directly influences the sustainable development of the nature, economy and society in Northwest China. Therefore, it is very necessary and impendency to reduce and control the water inrush disasters due to N2 Laterite destroyed by coal mining. Taking Yulin-Shendong mine area in Northern Shanxi Province as an example, centering on the issue of “mechanism of water inrush due to N2 Laterite destroyed by Jurassic coal mining”, this project studies the spatial occurrence and engineering geological properties of N2 Laterite. The formation process and patterns of water inrush disasters due to N2 Laterite destroyed by coal mining are studied by large scale physical and numerical simulation. The change characteristics and laws of soil structure and permeability of N2 Laterite due to being destroyed by coal mining are studied by analyzing stress and fractures evolution induced by mining, water-soil interaction and coal mining time effect. And then the relationship between soil structure and permeability are set up. The internal mechanism of water inrush and soil destroyed effect with time are revealed. The forecast theory and control technology of water inrush due to N2 Laterite destroyed by coal mining are put forward. It provide scientific basis for disaster prevention due to large scale coal mining in Northwest China. This project will contribute to the frontier researches on effect mechanism of human activity on the world environment.

新近系上新统N2红土是我国西北侏罗系煤层之上区域性分布的特殊土，是浅表层水体下的直接隔水层。随着西部煤炭资源开发规模扩大，N2红土层采动破坏突水及诱发浅表层生态地质环境灾害日益加剧，已严重影响区域经济可持续发展，减轻和防控N2红土采动破坏突水灾害已十分迫切和必要。本项目以陕北榆神矿区为例，围绕“N2红土采动破坏突水机理”这一科学问题，研究N2红土空间赋存及工程地质性质；通过大型物理模拟和数值仿真等，再现N2红土采动破坏突水过程与成灾模式；从采动应力-裂隙演化、水-土相互作用和采动时间效应（蠕变）方面，研究N2红土采动破坏结构-渗透性变化特征和规律，建立其采动结构变化与渗透性之间的关系式，揭示采动破坏突水及其时效演变内在机理；研究并提出N2红土采动破坏突水预报理论方法和防控技术措施，为我国西北大型煤炭开采灾害防治提供基础科学依据。研究成果将为人类活动对环境影响的机理这一前沿性研究作出贡献。

新近系上新统N2红土是我国西北侏罗系煤层之上区域性分布的特殊土，是浅表层水体（沙漠滩地潜水、地表水及黄土沟壑径流水等）下的直接隔水层；随着西北煤炭资源开发规模扩大，N2红土层采动破坏突水灾害及链生浅表层生态地质环境恶化日益加剧，已严重影响区域经济可持续发展。本项目主要以陕北榆（林）神（木）矿区为例，围绕“N2红土采动破坏突水机理及环境效应”这一科学问题，开展了“N2红土空间赋存、区域工程地质性质及孕灾模型，N2红土采动破坏突水模式，不同突水模式N2红土水-土相互作用及蠕变结构-渗透性变化特征规律，N2红土采动破坏突水评价及环境效应”研究。建立了“侏罗系煤层覆岩-N2红土复合结构导水裂隙带发育高度预计公式”，揭示了“N2红土采动破坏水-土相互作用、蠕变结构渗透性变化突水和渗漏过程机理”，发现“N2红土具有采动受损后自修复-即隔水性再造特性”，创建了“N2红土采动破坏突水环境工程地质模式”。成果为我国西北大型煤炭开采水害防治及生态环境保护提供了基础理论依据，具有重要的科学意义和应用价值。