宝日希勒露天煤矿内排土场稳定性研究.pdf

- I - 摘摘 要要 宝日希勒内排土场基底为煤层底板胶结好的深灰色泥岩、砂岩层和薄煤层，其倾向向南 与内排场推进方向基本相同，基底产状、岩性对内排土场稳定性极为不利，加之煤层承压水 向内排土场渗透、渗流，软化基底泥岩，形成演化弱层，降低排弃物抗剪强度，更加恶化了 内排土场稳定性。随着剥离破土动工、内排工作开展，内排土场的稳定性将继续威胁坑 下排水系统安全、内排工程安全和矿山安全生产，所以对内排基底稳定性和治理方案 研究具有重要现实意义和实用价值。 本文依据内排土场滑坡实际情况，采用自主开发计算软件，进行内排土场滑坡反 算，确定了基底演化弱层强度指标，同时采用 FLAC3D模拟软件对内排土场进行滑坡 模拟，进一步揭示了内排土场滑坡机理、滑坡模式，对内排土场稳定性做出了科学评 价，并研究设计了内排土场综合治理和稳定控制措施。 关键字关键字 露天矿；排土场边坡；数值模拟；刚体极限平衡法 - II - Abstract The dump basal of Baorixile open pit coal mine is cementation with dark mudstone, sandstone layer and sandstone layer on coal floor. Its tendency is roughly same with the inner advancing direction strie--south. The inner basement and lithologic is adverse to the inner basal stability. Furthermore, because of the coal confined water, basal mudstone is softening, ation and evolution into weak layer, reduce exhaust outcast shear strength, this makes the stability worse. As the peel ground-broken, inner work begins, the stability of Dump will continue making threat to the safty of drainage system and inner safety engineering even the safe production in mines. So it has the important practical significance and high economic efficiency in research of inner basal stability management. The paper according to the actual situation of dump landslide, using independent development software, do the numerical of dump landslide to make sure the intensity index of base evolution weak layer. At the same time, use FLAC3D to do numerical simulation of the dump landslide, further reveal the inner dump landslides landslide mechanism and mode. Make the scientific uation of its stability, within the proposed measures and comprehensive management dump, make sure the safty of drainage system and inner safety engineering also the safe production in mines. Key Wordsopen pit coal mine；dump slope；numerical simulation；rigid body limit equilibrium - III - 目目 录录 摘 要.............................................................................................................................................Ⅰ Abstract...............................................................................................................................................Ⅱ 1 绪论...................................................................................................................................................1 1.1 问题提出及研究意义 ...................................................................................................................1 1.2 国内外边坡稳定性分析的现状...................................................................................................3 1.3 主要研究内容及方法..................................................................................................................7 1.3.1 排土场稳定性研究内容 ...................................................................................................7 1.3.2 内排土场边坡稳定性研究方法和理论 ...........................................................................7 1.3.3 内排土场边坡滑坡防治措施 ...........................................................................................8 1.4 论文的技术路线.........................................................................................................................8 2 矿区工程、水文地质概述.............................................................................................................9 2.1 边坡岩体的工程地质特征 ..........................................................................................................9 2.1.1 地层及岩石的工程地质特征 .........................................................................................9 2.1.2 各煤层顶底板岩石工程地质特征 ...............................................................................10 2.1.3 剥离物强度厚度及其分布 ...........................................................................................11 2.1.4 坚硬岩石的赋存情况 ...................................................................................................11 2.2 矿区水文地质特征 ...................................................................................................................11 2.2.1 第四系孔隙潜水含水层 ...............................................................................................11 2.2.2 裂隙孔隙承压含水层............................................................................................12 2.3 首采区工程地质、水文地质条件对内排土场稳定性影响.........................................................12 3 内排土场边坡稳定性分析...........................................................................................................14 3.1 内排土场滑坡主要原因分析.....................................................................................................14 3.2 滑坡反分析 ..............................................................................................................................16 3.2.1 极限平衡法基本原则 ...................................................................................................16 3.2.2 排弃物、基底泥岩物理力学指标确定 .......................................................................17 3.2.3 内排土场滑坡反算 .......................................................................................................18 3.3 确定内排土场帮坡角 .................................................................................................................18 4 内排土场滑坡机理 FLAC3D数值模拟 ..........................................................................................20 4.1 FLAC3D简介 ..............................................................................................................................20 - IV - 4.2 FLAC3D理论基础.......................................................................................................................20 4.2.1 增量弹性法则 ...............................................................................................................20 4.2.2 屈服函数和势函数 .......................................................................................................21 4.2.3 塑性修正 .......................................................................................................................23 4.2.4 强度折减法的计算原理 ...............................................................................................24 4.3 内排土场稳定性数值模拟 ........................................................................................................25 4.3.1 内排土场稳定性数值模拟模型的确定 .......................................................................25 4.3.2 数值模拟相关初始参数的确定 ...................................................................................25 4.3.3 数值模拟结果分析 .......................................................................................................26 4.4 小结 .........................................................................................................................................31 5 防治措施.......................................................................................................................................32 5.1 滑坡灾害评估...........................................................................................................................32 5.2 防治措施..................................................................................................................................32 5.2.1 地下水疏干 ...................................................................................................................32 5.2.2 内排土场排土强度控制 ...............................................................................................40 5.2.3 排土场基底改造 ...........................................................................................................42 6 结论与展望...................................................................................................................................43 6.1 结论 .........................................................................................................................................43 6.2 展望 .........................................................................................................................................43 参考文献.............................................................................................................................................44 作 者 简 历.........................................................................................................................................46 学位论文数据集...................................................................................................................................48 - 1 - 1 绪论 1 绪论 1.1 问题提出及研究意义 1.1 问题提出及研究意义 宝日希勒露天矿地理上位于莫勒格尔河和海拉尔河之间，地形起伏呈缓坡状，地面海 拔标高程 724.09～601.88m，北东高，南西低，属内蒙古高原面上的剥蚀残丘地貌。露天 煤矿原设计年产原煤 1.8Mt/a，开采工艺为单斗挖掘机自卸卡车间断工艺，2008 年扩 能为 10 Mt/a 的大型露天煤矿。露天矿主采煤层为 12煤,煤的品种为褐煤，煤层呈近水平赋 存，首采区煤层向西南倾斜，倾角 0～5。剥离物主要为第四系腐植土、亚砂土、亚粘土、 砂砾岩等。地表水系有莫勒格尔河从露天矿采场西北部流过。地下水主要是第四系孔隙含 水层和煤层裂隙含水层。 露天煤矿从 2004 年至 2006 年开始进行初期试验性内排，随内排工程量增加，内排强 度逐渐增大，目前基本实现全部内排，如图 1.1 所示。内排土场基底为煤层底板胶结好的 深灰色泥岩、砂岩层和薄煤层，其倾向向南与内排土场推进方向基本相同，基底产状、岩 性对内排土场稳定性极为不利，加之煤层承压水向内排土场渗透、渗流，软化基底泥岩， 降低排弃物抗剪强度，更加恶化了内排土场稳定性。2005 年 11 月、2006 年 5 月，发生 2 次内排土场失稳现象（如图 1.2 所示） 。滑坡发生后采取了在煤层底板开挖输水盲沟网、内 排土场帮坡角由 18降低为 16等综合治理措施，取得了一定效果。 699.328 548.992 547.512 586.112 586.213 586.103 586.133 589.719 586.832 586.978 587.187 587.860 581.982 582.254 582.247 583.165 583.855 582.406 584.657 584.283 582.144 583.737 583.372 582.201 583.002 582.699 582.028 582.234 582.807 563.970 564.612 562.084 562.255 562.589 563.100 563.578 564.306 566.532 568.288 568.869 568.904 569.492 569.671 570.210 570.013 570.311 570.153 570.235570.342 570.170 570.242 570.446 571.791 569.346 572.713 571.538 571.319 570.837 570.935 570.385 570.414 570.070 570.027 569.772 568.363 567.279 566.249 565.269 563.325 563.596 563.152 562.530 562.414 574.744 563.478 574.868 564.210 564.127 566.231 565.875 565.193 567.809 568.104 568.483 569.774 570.741 570.144 570.026 571.089 570.470 570.131 570.113 570.299 569.877 571.055 570.361 570.657 571.098 570.993 569.900 570.213 570.830 570.434 574.914 575.438 554.400 575.077 575.489 554.831 571.089 570.328 570.113 570.787 553.356 552.664 554.120 564.210 564.487 564.884 562.864 562.176 563.198 559.312559.706 560.377 561.897 555.619 561.857 555.055 554.603 554.797 556.018 554.719 645.806 584.396 586.676 629.641 576.013 575.932 575.909 569.433 569.953 567.663 567.786 576.030 575.498 574.439 647.329 617.121 616.792 552.894 553.160 553.075 554.248 553.671 562.833 562.728 563.863 573.025 572.332 548.704 548.239548.317 548.152 548.665 548.724 552.453 556.096 555.214 554.153551.314 554.205 553.963 554.033 553.817 552.460 551.940 552.049 552.836 552.184 552.051 549.410 548.610 548.781 549.274 550.244 548.044 548.458 549.219 549.463 水 圈 552.669 552.434 554.428 556.474 554.003 579.115 579.158 580.303 581.179 580.138 576.912 577.814 579.254 578.112 579.563580.118 580.769 579.176 580.168 580.070 580.671581.445 581.680 581.964 581.729 580.004 581.715 581.203 582.641 586.258 588.235 594.741 596.359 595.107 595.215 596.024 595.735 595.387 593.134 593.052 592.387 593.482 593.021 593.188 594.150 591.038 591.803 591.576 588.669 590.800592.634 586.801 589.105 554.378 554.992 556.640 553.458 558.560 553.458 553.220 105电 铲 558.825 555.137 553.978 548.702 548.165 548.102 551.741 551.040 547.995 710.608 710.768 711.326 710.439 709.217 703.790702.915 703.208 703.545 704.214 705.444706.591 706.486 707.040 706.204 706.120 705.713 673.006 673.010 673.167 673.605 674.232 674.200 675.143 675.159 675.773 675.884 676.544 678.578 679.354 681.302 682.699 683.149 683.342 680.816 682.997 685.045 685.888 685.051 685.304 685.047 684.965 684.237 684.075 683.898 683.511 682.699 684.431 684.704685.104 685.861 691.000 691.838 675.801 676.877 676.928676.913 675.665 676.062 675.967 677.291 677.722 676.458 675.311 674.411 673.488 672.340 670.814 670.698 670.292 669.375 668.500 668.116 667.853 667.622 666.791 667.270 667.198 667.282 666.911 667.975 668.989 669.726 669.535 668.450 667.498 667.282 667.485 662.556 663.012 662.665 662.996 655.604 655.345 656.760 656.765657.053 657.556 656.930 654.482 655.581 656.828 702.700 702.787 705.755 705.887 668.119 667.831 669.352 670.707 672.904 675.860 676.298 676.840 676.611 674.663 673.004 671.454 670.800 670.599 662.766 655.219 656.484 656.466 657.047 649.910 650.048 650.262 649.911 652.721 653.337 651.543 651.527 651.970 645.434 647.706 645.239 646.146 643.480 643.898 640.898 637.930 646.525 643.818 643.867 630.008 632.447 633.617 633.835 633.160 634.204 634.243 633.234 633.931 645.952 644.193 644.787 644.895 644.694 645.529 645.536 645.717 646.734 645.905 646.910 646.553 647.925 647.479 648.595 647.505 648.653 647.733 649.411 648.312 651.232 647.910 651.691 648.423 651.859 649.416 650.212 650.788 651.371 649.278 651.318 649.497 651.970 649.901 649.485 650.511 650.486 652.270 650.418 650.148 575.194 651.212 648.711 648.603 646.704 645.538 644.108 651.302651.321 649.275 649.208 649.211 水泵房 582.253 582.815 586.258594.741 590.021 595.681 595.934 592.464 587.884 587.835 587.497 588.590 587.456 589.914 587.852 591.605 587.810 588.023 588.033 582.959 588.603 577.259 589.189 578.840 590.824 577.495 591.037 592.869 577.539 592.973 576.291 587.356 576.228 576.813 582.357 575.408 576.451 571.808 575.242 576.169 572.451 577.559 573.915 578.528 573.183 577.489 576.441 572.873 572.919 575.571 580.064 572.553 581.333 571.621 581.877 570.714 582.153 570.950 581.687 570.463 583.074 567.670 582.580 567.170 563.546 581.821 564.817 580.059 565.891 575.958 565.168 576.191 567.502 574.676 574.966 570.203 574.938 570.669 575.509 571.231 575.574 570.361 571.546 575.162 577.662 575.431 580.585 580.348 575.115 580.857 576.117 580.626 576.813 580.582 581.181 580.147 580.801 581.209 582.765 581.461 580.894 580.209 581.827 580.405 578.292 569.383 572.345 571.483 576.263 570.469 575.725 570.295 575.566 570.092 575.761 576.037 569.235 576.614 568.983 576.523 567.896 568.279 581.403 569.005 569.427 568.839 568.810 568.044 568.061 568.216 567.877 567.467 565.278 563.708 576.641 576.936 562.342 561.932 569.296 562.419 561.803 561.920 562.566 567.606 569.505 569.461 568.592 568.416 571.961 575.676 575.139 572.125 578.996 567.701 567.563 564.173 563.648 560.888 560.060 559.894 560.602 559.849 559.524 559.783 558.521 558.663 557.979 558.545 556.035 550.981 551.053 552.035 552.014 548.995 549.066 551.359 551.155 560.690 551.095 628.223 558.805 628.176 628.024 573.749 574.026 573.852 572.298 562.755 559.369 562.489 558.360 561.022 557.952 561.650 557.590 561.052 557.137 561.408 557.635 569.235 575.077 570.837 548.995 548.093 547.122 547.995 547.394 548.702 548.093 562.342 562.566 555.878 587.884 587.810 588.033 588.603 590.824 592.869 592.973 588.590 589.914 549.999 550.300 551.196 552.428 552.904 554.598 557.202 557.270 内排变形坡底线 647.600647.600 645.974 650.535 652.418 657.772 661.634 662.885 665.466 666.835 667.634 663.461 661.462 图 1.1 2009 年内排土场平面图 Fig. 1.1 Inner dump plan in 2009 - 2 - 图 1.2 内排土场滑坡照片 Fig. 1.2 Dump photo in landslides 随排弃强度增大，自 2009 年 4 月 28 日起内排土场有明显沉降，至 5 月 2 日内排土场 660 水平沉降加剧并有明显位移，内排土场开始滑坡，持续时间 1～2 小时。滑坡区域东 西长约 630m，南北长约 750m，滑坡区域面积