Estimation and application of local replacement rate for soft foundation in inner dump based on strength parameters: A case study of Baiyinhua No. 1 open-pit mine in Inner Mongolia
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摘要:
为了更加经济有效地提高软基底内排土场边坡稳定性，以白音华一号露天矿为工程背景，通过直剪试验测定了排弃物-弱层接触面和排弃物-砂岩接触面抗剪力学指标，提出了局部换填条件下排弃物与基底接触面的等效抗剪力学参数的确定方法；基于刚体极限平衡理论，计算不同换填率条件下的边坡稳定系数，以安全储备系数为限定条件提出了基于强度参数的内排土场软基底局部换填率估算方法，并采用数值模拟手段进行验证。研究结果表明：确定白音华一号露天矿排弃物-砂岩接触面的黏聚力为25.78 kPa，内摩擦角为17.58°；排弃物-弱层接触面的黏聚力为7.50 kPa，内摩擦角为9.72°；局部换填情况下软基底内排土场边坡稳定性系数与换填率呈正相关一次函数关系；计算求得满足安全储备系数要求的内排土场某阶段基底换填率为20%；局部换填处理后软基底内排土场边坡的滑坡模式仍为以圆弧为侧界面、基底弱层为底界面的组合滑动。
Abstract:In order to effectively enhance the stability of the slope within the soft base of the inner dump, this study focuses on the Baiyinhua No. 1 open-pit mine as the engineering background. Through direct shear tests, the shear mechanical characteristics of the waste-weak layer interface and the waste-sandstone interface were determined. A methodology is proposed to determine the equivalent shear mechanical parameters of the waste-base interface under localized replacement conditions. In this study, the limit equilibrium theory of rigid body is applied to calculate the slope stability coefficients under different replacement ratios. Additionally, an estimation method for the local replacement ratio of the soft base in the waste dump, based on strength parameters and subject to a safety reserve coefficient constraint, was put forward and verified using numerical simulations. The results indicate that the cohesive force and internal friction angle at the waste-sandstone interface in the Baiyinhua No.1 open-pit mine were determined to be 25.78 kPa and 17.58°, respectively. These two parameters at the waste-weak layer interface were found to be 7.50 kPa and 9.72°, respectively. A positive linear relationship was observed between the stability coefficient of the inner dump slope in the soft base under localized replacement conditions and the replacement ratio. The calculated results reveal that a replacement ratio of 20% for a certain stage of the dump's base satisfies the safety reserve coefficient requirement. After local replacement treatment, the landslide mode of the dump slope in the soft foundation remains characterized by combined sliding, with the arc acting as the lateral boundary and the weak base layer serving as the bottom interface.
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Key words:
- inner dumps /
- side slope /
- stability /
- soft substrate /
- contact surface /
- local replacement
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表 1 岩土体物理力学指标
Table 1. Physical and mechanical properties of soil strata
岩体名称 内摩擦角/（°） 黏聚力/kPa 容重/ （kN·m−3） 排弃物 17.49 25.38 17.80 第四系砂土 23.98 0.00 17.50 新近系古近系黏土 24.00 85.00 19.30 煤 26.32 58.00 11.90 砂岩 17.76 50 20.4 泥岩 21.85 26.00 20.10 
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表 2 岩样天然含水率测定成果
Table 2. Measurement results of natural moisture content of rock samples
岩石名称 烘干前
质量/g烘干后
质量/g含水率/% 排弃物 40.32 38.69 4.20 泥岩 33.74 30.73 9.79 弱层 28.31 23.16 22.24
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表 3 烘干岩样各粒径级配比
Table 3. Particle Size Distribution of dried rock samples
岩性 各粒径占总质量百分比/% >2 mm 1～2 mm 0.5～1 mm 0.25～0.5 mm 0.075～0.25 mm <0.075mm 排弃物 4.711 14.317 33.268 13.842 22.515 11.347 碳质泥岩 11.037 27.413 26.346 11.927 16.318 6.959 泥岩 21.344 14.625 26.383 10.968 18.182 8.498
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表 4 不同换填率条件下接触面等效抗剪力学指标
Table 4. Equivalent shear mechanical parameters of contact surface under different replacement rates
基底换填率/% 黏聚力/kPa 内摩擦角/（°） 0 7.500 9.720 10 9.328 10.528 20 11.156 11.332 30 12.984 12.131 40 14.812 12.926 50 16.640 13.716 60 18.468 14.500 70 20.296 15.279 80 22.124 16.052 90 23.952 16.819 100 25.780 17.580
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[1] 李广贺. 内排土场支挡煤柱力学效应及其应用研究[D]. 阜新: 辽宁工程技术大学, 2021
LI Guanghe. Study on mechanical effect and application of supporting coal pillar in internal dump[D]. Fuxin: Liaoning Technical University, 2021. （in Chinese with English abstract）
[2] 张萌,刘宏磊,乔文光,等. 排土场稳定性影响因素显著性研究[J]. 中国安全科学学报,2021,31(2):69 − 75. [ZHANG Meng,LIU Honglei,QIAO Wenguang,et al. Significant research on influencing factors of dump stability[J]. China Safety Science Journal,2021,31(2):69 − 75. (in Chinese with English abstract)
ZHANG Meng, LIU Honglei, QIAO Wenguang, et al. Significant research on influencing factors of dump stability[J]. China Safety Science Journal, 2021, 31（2）: 69-75. （in Chinese with English abstract）
[3] POULSEN B,KHANAL M,RAO A M,et al. Mine overburden dump failure:A case study[J]. Geotechnical and Geological Engineering,2014,32(2):297 − 309. doi: 10.1007/s10706-013-9714-7
[4] KAINTHOLA A,VERMA D,GUPTE S S,et al. A coal mine dump stability analysis:A case study[J]. Geomaterials,2011,1(1):1 − 13. doi: 10.4236/gm.2011.11001
[5] 王家臣,陈冲. 软弱基底排土场边坡稳定性三维反演分析[J]. 中国矿业大学学报,2017,46(3):474 − 479. [WANG Jiachen,CHEN Chong. Three dimensional back analysis for stability of slope dumped on weak basement[J]. Journal of China University of Mining & Technology,2017,46(3):474 − 479. (in Chinese with English abstract)
WANG Jiachen, CHEN Chong. Three dimensional back analysis for stability of slope dumped on weak basement[J]. Journal of China University of Mining & Technology, 2017, 46（3）: 474-479. （in Chinese with English abstract）
[6] 王家臣,李阳春,徐文彬,等. 软-陡基底排土场边坡破坏模式与机理[J]. 矿业科学学报,2021,6(2):139 − 147. [WANG Jiachen,LI Yangchun,XU Wenbin,et al. Failure mode and mechanism of mine waste dump with a soft and steep layer base[J]. Journal of Mining Science and Technology,2021,6(2):139 − 147. (in Chinese with English abstract)
WANG Jiachen, LI Yangchun, XU Wenbin, et al. Failure mode and mechanism of mine waste dump with a soft and steep layer base[J]. Journal of Mining Science and Technology, 2021, 6（2）139-147（in Chinese with English abstract）
[7] 陈冲,张军. 倾斜基底排土场边坡变形破坏底面摩擦模型实验研究[J]. 金属矿山,2016(10):150 − 154. [CHEN Chong,ZHANG Jun. Experiment on deformation and failure features of waste-dump slope based on inclined and weak layer by the floor friction model[J]. Metal Mine,2016(10):150 − 154. (in Chinese with English abstract)
CHEN Chong, ZHANG Jun. Experiment on deformation and failure features of waste-dump slope based on inclined and weak layer by the floor friction model[J]. Metal Mine, 2016（10）: 150-154. （in Chinese with English abstract）
[8] 赵红泽,邵志奔,杜海瑞,等. 露天矿背斜区内排土场边坡基底处理方式优选研究[J]. 煤炭科学技术,2021,49(2):77 − 84. [ZHAO Hongze,SHAO Zhiben,DU Hairui,et al. Study on optimization of treatment methods for inclined basement of inner dump slope in anticline area of open-pit mine[J]. Coal Science and Technology,2021,49(2):77 − 84. (in Chinese with English abstract)
ZHAO Hongze, SHAO Zhiben, DU Hairui, et al. Study on optimization of treatment methods for inclined basement of inner dump slope in anticline area of open-pit mine[J]. Coal Science and Technology, 2021, 49（2）77-84（in Chinese with English abstract）
[9] NI Fulai,WEN Xin,ZHANG Xiaobin,et al. Experimental study on vacuum dynamic consolidation treatment of soft soil foundation[J]. IOP Conference Series:Materials Science and Engineering,2017,269:012009. doi: 10.1088/1757-899X/269/1/012009
[10] 闫澍旺,陈静,孙立强,等. 抛石挤淤深度的计算方法和模型试验[J]. 岩土力学,2015,36(增刊 1):43 − 48. [YAN Shuwang,CHEN Jing,SUN Liqiang,et al. Calculation method and model test on penetration depth of squeezing soft clay (with stone) method[J]. Rock and Soil Mechanics,2015,36(Sup 1):43 − 48. (in Chinese with English abstract)
YAN Shuwang, CHEN Jing, SUN Liqiang, et al. Calculation method and model test on penetration depth of squeezing soft clay（with stone） method[J]. Rock and Soil Mechanics, 2015, 36（S1）: 43-48. （in Chinese with English abstract）
[11] YEE Y W,YOHANNES M M. Interactive geotechnical design in Karst and ex-mining ground in Malaysia[J]. Geotechnical Research,2018,5(3):182 − 196. doi: 10.1680/jgere.18.00006
[12] 徐奴文,唐春安,唐世斌,等. 考虑弱层置换的岩石边坡稳定性分析[J]. 岩土力学,2011,32(增刊 1):495 − 500. [XU Nuwen,TANG Chun'an,TANG Shibin,et al. Stability analysis of rock slope considering weak-layers replacement[J]. Rock and Soil Mechanics,2011,32(Sup 1):495 − 500. (in Chinese with English abstract)
XU Nuwen, TANG Chun'an, TANG Shibin, et al. Stability analysis of rock slope considering weak-layers replacement[J]. Rock and Soil Mechanics, 2011, 32（S1）: 495-500. （in Chinese with English abstract）
[13] 赵丹旗,付昱凯,侯晓坤,等. 不同应力路径下饱和重塑黄土的力学特性[J]. 水文地质工程地质,2022,49(6):74 − 80. [ZHAO Danqi,FU Yukai,HOU Xiaokun,et al. Mechanical properties of saturated remolded loess under different stress paths[J]. Hydrogeology & Engineering Geology,2022,49(6):74 − 80. (in Chinese with English abstract) doi: 10.16030/j.cnki.issn.1000-3665.202201020
ZHAO Danqi, FU Yukai, HOU Xiaokun, et al. Mechanical properties of saturated remolded loess under different stress paths[J]. Hydrogeology & Engineering Geology, 2022, 49（6）: 74-80. （in Chinese with English abstract） doi: 10.16030/j.cnki.issn.1000-3665.202201020
[14] 周旭宽. 非饱和土与结构接触面的力学特性研究[D]. 北京: 北京交通大学, 2021
ZHOU Xukuan. Study on mechanical properties of interface between unsaturated soil and structure[D]. Beijing: Beijing Jiaotong University, 2021. （in Chinese with English abstract）
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