风积沙煤矿区高强度开采土地破坏机理及其预测方法

As the coal industry moves to west ecological fragile areas under the country strategy, the surface environment may be deteriorated by high tension coal mining, with reverse succession. Compare with the mature eastern coal mining area, the land damage features, destroy mechanism and other scientific problems in windy and sandy area with high strength coal mining has not been solved. Based on previous research, utilization of surveying and mapping, mining subsidence and geology, the evolution characteristic of surface environment of typical coal faces in Shendong coalfield will be dynamic monitored and simulated, in the whole process of land damage. Three key aspects will be researched in this project: (1) The surface subsidence laws and features will be studied, and surface movement and deformation angle parameters and probability integral prediction parameters will also be found by the analyzing the measured data and test results. Then the mechanism of surface subsidence caused by aeolian sandy layer and large coal face can be revealed.(2)The distribution characteristic and development rules of ground fissures due to rapid mining will be studied, and their relationship with mining geological conditions also will be established by measured data. The development mechanism of ground fissures will be revealed by analyzing the evolution laws of displacement field, destruction field and stress field of the overlaying key strata during mining.(3)Based on (1) and (2),the land damage prediction model will be built, according to the linkage mechanism between land damage characterization parameter and mining methods, some ecological restoration principles and strategies also will be presented. This project not only can reveal the land damage mechanism in windy and sandy area, but also provide a new win-win way to achieve coal mining and environment protection.

煤炭行业的战略西移以及高强度的开采方式，可能诱发地表环境恶化，促使其逆向演替，相对于中东部矿区，风积沙煤矿区高强度开采土地的受损特征、破坏机理等科学问题没有得到很好的解决。立足以上不足，本项目从工作面尺度出发，利用测绘学、开采沉陷学、地质学等相关理论，采用野外动态监测和室内模拟等手段，研究风积沙区高强度开采条件下地表移动变形规律和特点，找出地表移动变形的角量参数和概率积分预计参数，分析风积沙层、超大工作面对地表移动规律的作用机理；研究快速开采方式下地裂缝的发生发育规律，建立地裂缝发育过程与采矿地质条件间的相关关系，通过采动过程中覆岩位移场、破坏场和应力场的演化规律，揭示关键层控制条件下地裂缝发育规律的成因机制；进而获取开采沉陷土地破坏表征参数与开采方式间的联动机理，建立土地损毁的预测模型与方法，提出风积沙区采煤沉陷土地生态修复的原理与策略，为生态脆弱区煤炭开采与环境保护提供相应的理论依据。

煤炭行业的战略西移以及大规模、现代化高强度的开采方式，必然导致地表生态环境的破坏范围广、速度快、形式多、时空差异大。对于西北矿区，自身的生态环境相对脆弱，抗扰动能力差,特别是在内蒙的神东矿区，这种“逆向”分布的特征更为明显。大规模的资源开采可能诱发地表环境恶化促使其逆向演替。土地作为生态环境的载体，高强度开采对其破坏机理及其相应的修复策略的研究具有明显的现实意义。针对于上述问题，本研究围绕监测理论与方法，采用现场监测、信息技术、遥感等手段，开展了一系列的研究，具体内容如下：（1）构建了神东矿区典型工作面开采前后土地生态环境演变特征的监测方法，发明了采动损害的现场以及室内模拟的监测装置，研发监测数据的采集方法和分析软件，基于神东矿区部分工作面的地表移动变形实际观测数据，获取了地表移动变形参数与预计模型，发现了神东矿区坚硬覆岩条件下地表移动变形的共性；（2）揭示了动态地裂缝快速闭合的自修复特征，建立了动态地裂缝的发育周期与采矿地质条件的函数模型，发现了边缘地裂缝从“椭圆型-圆型-O型”三个连续阶段的发育过程，揭示了风积沙松散层存在的条件下，边缘地裂缝向工作面内部收缩、裂缝角呈现近似垂直角的分布特征；（3）在工作面尺度上，通过开采沉陷模拟以及研究区域采动前后典型样区的现场取样，定量分析了高强度大工作面开采技术下，地表沉陷、移动变形以及土壤理化特性的自修复特征；（4）在矿区尺度上，利用遥感技术，研发了一种影像自动配准方法，结合开采沉陷规律，综合利用地表移动变形参数、地形因子、土地利用现状等参数，构建了矿区采动前后的地表生态环境的演变特征的评价模型，提出了分区域、差异性的生态环境修复模式。研究结果表明，高强度大工作面开采，减少了地表重复扰动次数、缩短了采动影响的时长，使部分土地损毁参数呈现了快速“自修复”特征，可为生态脆弱区的煤炭资源与环境的协调开发提供一定的参考。