【作者】 尚慧；

【导师】 倪万魁；

【作者基本信息】 长安大学 ， 地质工程， 2013， 博士

【摘要】 本文在查明宁夏全区存在的主要矿山地质环境问题及潜在危害的基础上，基于ArcGIS，采用综合评判法对宁夏全区的矿山地质环境进行了量化分区评价，并分析了矿山地质环境问题的发展趋势；建立了宁夏石嘴山矿区的GPS变形监测系统，该系统可对矿区地表变形进行实时自动化监测；应用遥感技术实现了石嘴山矿区生态环境动态监测；采用两时相DEM叠加、数值模拟及概率积分法分析了石嘴山矿区地表变形特征，预测了地面塌陷发展趋势，并通过对代表性剖面的有限元数值模拟，揭示了采空区覆岩应力分布和变形破坏机理。从而为宁夏矿山地质环境评价、监测和地面塌陷机理研究提供了新思路和新方法，并对合理开发矿产资源、有效保护矿山地质环境和矿山生态的恢复与重建有重要参考价值与实践意义。取得的主要研究成果如下：（1）在查明宁夏全区存在的主要矿山地质环境问题基础上，依据各类矿山地质环境问题分布、现状及发展趋势，遵循可比性、简要性、整体性和可操作性原则，建立了包括地质环境条件、地质灾害、矿山开采状况、资源损毁、三废排放、水环境影响和环境治理率7项准则层和21项指标层的评价指标体系。（2）基于ArcGIS，采用综合评判法对宁夏全区的矿山地质环境进行了量化评价，其中各评价指标权重运用层次分析法与粗糙集理论相结合的组合赋权法确定。参考量化评价结果，结合实地调查资料，将全区矿山地质环境划分为影响严重区、较严重区和较轻区3个大区34个亚区，并对各亚区的地质环境背景、主要矿山环境地质问题及其危害进行了综合评述。（3）建立了石嘴山矿区GPS变形监测系统。在该矿区共布设了1个GPS参考站、67个GPS监测点及16个传统大地测量监测点，重点介绍了该监测系统的技术指标，整体设计、包含的各子系统及自动化监测的实现过程。（4）运用遥感技术实现了石嘴山矿区生态环境的动态监测。分别选取该矿区开采初期、矿山地质环境治理前、治理后三期遥感影像数据进行解译，并对解译成果进行叠加，得到地类动态变化图和矩阵，解译分析结果表明：上世纪70年代到2003年间，耕地和植被覆盖区面积急剧减小，向荒地及城镇居民点的转化尤为明显，这主要是由城市化进程中基础设施建设及水土流失造成；煤堆、水体、矸石山等面积都呈快速增长的趋势，主要由荒地转化而来，是采矿活动造成，矿区的环境遭到严重破坏。2003年到2009年间，植被覆盖区面积的增速最快，主要由荒地和城镇居民点转化而来，而矸石山、荒地等覆被面积都有明显减少，矿区生态环境得到很大改善，显示出地质环境治理恢复的成效。（5）选取石嘴山矿区两时相DEM数据进行叠加分析，得到了地表高程的变化情况：上世纪70年代~2003年间，矿区高程最大下降幅度为27.5m，沉降量较大的都分布在塌陷坑处，高程下降10~27.5m，并得到了七个较大塌陷坑的最大垂直位移和塌陷范围。同时选取4个典型剖面，对两时相地形线进行叠加分析，与塌陷坑相对应，得到了更为直观的地面塌陷位移与范围变化情况。（6）选取石嘴山矿区三个典型剖面，按照矿区实际开采情况，建立了离散元开采沉陷模型，得到了各开采水平的最大垂直位移和塌陷范围；采用概率积分法预计矿区走向主断面和倾向主断面的地表变形情况，得到的计算结果与数值模拟及不同时相DEM叠加结果基本一致，并预测当采深采厚比大于120时，采矿活动对地表的影响逐渐减小，引发地面塌陷及地裂缝的可能性变小，逐渐趋于稳定。（7）通过对石嘴山矿区典型剖面进行有限元数值模拟，揭示了开采过程中覆岩的应力变化特征和分布规律，并采用格里菲斯强度判据分析了地面塌陷的力学机制。更多还原

【Abstract】 Based on finding out the main mining geo-environmental problems and its potentialhazards, the mining geo-environment of Ningxia was evaluated by use of comprehensiveassessment method on ArcGIS. Referred to the quantitative evaluation results, the mininggeo-environment problems of Ningxia zonation was comprehensively evaluated and itsdevelopment trend was analyzed. The GPS deformation monitoring system was established inShizuishan mining area and deformation could be monitored automatically and uninterrupted.The ecological environment of Shizuishan mining area was dynamiccally monitored byapplication of remote sensing technology. In this paper, the surface deformation in Shizuishanmining area was analyzed by means of superposition of two different period DEM, numericalsimulation and probability integration method, the trends of ground subsidence was predictedas well. One typical profile was selected and finite element models was simulated to indicatethe stress changes in overlying rocks and to reveal deformation characteristics. Mechanism ofground subsidence was analyzed to set an example for evaluating of mining geo-environmentin Ningxia. New ideas and new methods were provided for mine geo-environment monitoringand the study of ground subsidence mechanism. Therefore, the study was of importantacademic significance and application value on rational exploration of mineral resources, andmuch contribution to the effective protection of the mining geo-environment and ecologicalrecovery. The main conclusions are as follows:(1) Based on finding out the main mining geo-environmental problems in Ningxia,evaluation index system was established following principles of comparability, briefly,integrity and operability, according to distribution, present situation and development trend ofvarious types of geo-environment problems. It includes7criteria layers and21indicator layers. The criteria layers consisted of geological environment conditions, geological disasters,mining conditions, resource damage, waste discharge, water environmental impacts andenvironmental governance rate.(2) Mining geological environment of Ningxia was quantitatively evaluated by use of comprehensive evaluation method based on ArcGIS. The weight of evaluation index wascalculated combining AHP with rough set theory. Based on quantitative evaluation results andfield survey data, the study area was divided into3regions and34sub-regions, namely theseriously influenced area, the more serious influenced area and the lighter influenced area.The geological environment background and main mining geo-environmental problems ofeach sub-region were reviewed comprehensively.(3) GPS deformation monitoring system was established in Shizuishan mineral area. OneGPS reference station,67GPS monitoring stations and16traditional geodetic monitoringpoints were set up in the area. The technical indicators, the overall design, various subsystemsand the implementation process of automated monitoring were mainly introduced in thepaper.(4) Dynamic monitoring of the ecological environment in Shizuishan mining area hadbeen achieved by using remote sensing technology. Three period remote sensing image datawere interpreted and superimposed respectively, obtaining the dynamic changes of the landtype map and matrix. Analysis of the interpretation results showed that: firstly, from1970s to2003, the main change of lands in Shizuishan mining area was that vegetation coverage areaand cultivated land had been transformed to residential areas and wastelands by infrastructureconstruction and soil erosion. What’s more, the areas of gangue, coal pile, water etc. increasedgreatly because of mining activities. Secondly, the areas of vegetation coverage area increasedthe fastest during2003to2009from wasteland and residential areas whereas areas such asgangue and coal pile decreased sharply as a result of integrated renovation of mininggeo-environment.(5) Changes of surface elevation were obtained by overlay analysis of two period DEMdata of Shizuishan mining area. It could be summarized as: from1970s to2003, the largestdecline of the elevation was27.5m. Larger subsidence areas were located at the collapse pitwith the elevation decreasing from10to27.5m leading to the maximum vertical displacementand collapse range of seven large collapse pits. More intuitive changes of the displacementand range of ground subsidence were obtained by overlay analysis of two period topographic lines by selecting four typical profiles with correspondence to the collapse pit.(6) Discrete element model of three typical cross-sections in Shizuishan mining areawere established to obtain the maximum vertical displacement and the collapse range of eachmining level in accordance with the actual mining condition. The surface deformation of themain strike section and inclination section were predicted by use of probability integrationmethod. The calculated results were in consistence with the numerical simulation and DEMsuperimposed results. It can be deduced that the impact of mining activity on the surfacedeformation would gradually decrease when the ratio of the mining depth and thickness wasgreater than120and the possibility of causing ground subsidence and cracks would becomesmaller, gradually becoming stabilized.(7) The variation and distribution of the rock stress in the mining process were analyzedaccording to establish two-dimensional finite element numerical simulation model of threetypical cross-sections in Shizuishan mining area. The deformation characteristics and failuremechanism of the overburden rocks were revealed combining with the geological conditionsand mining current situation.更多还原