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| Experimental research on reinforcement mechanism of geogrid in open-pit dump |
| SUN Shuwei,PANG Bo,LIU Liu,YANG Zhaoxi |
| (School of Energy and Mining Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China) |
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Abstract A series of base frictional tests were conducted to study the failure process of mine waste dump reinforced with geogrid under various conditions. By the image speckle analysis and point-tracking technology,the displacements and strains of mine waste dump were obtained,and the failure mode,stability of the dump and mechanism of the geogrid were analyzed. The results show:(1) When there is no geogrid or the length of the grogrid is insufficient,the mine waste dump will suffer deep failure,showing an integral arc sliding from bottom to top. When the full-length geogrid is used,the failure mode of the dump changes from the overall failure to local failure,and the shear effect of the shallow layer of the slope becomes more significant when the bench slope is steeper. (2) The deformation process of the dump can be divided into three stages. The first stage is the uniform deformation stage,and the displacement of the measuring points is small. The second stage is the deformation localization stage,in which some measuring points produce displacement acceleration and slip crack forms inside the model. The third stage is the failure stage,where the displacement of the measuring point shows a bifurcation phenomenon. To be specific,the displacement of the measuring point of the sliding body continues to increase,while the displacement of the measuring point in the stable body tends to be constant. The geogrid has a significant control effect on the deformation of the dump. (3) The initial cracking time and local failure time are taken as the evaluation index to study the stability of geogrid-reinforced dump. The geogrid can be used not only to improve the dump stability,but also to expand the volume of the dump. Taking Model A1 and B1 in this study as examples,the dump expands the volume by about 6.33% with geogrid reinforcement under the promise of ensuring stability. (4) For high and steep dumps with weak foundations,we recommend using full-length geogrid;however,for dumps with fine foundations and smaller heights,the length of geogrid can be reduced to save costs according to the practice. The results have guiding significance for the stability and expansion of the dump and saving the land area of the mining area.
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| [1] 王家臣,孙书伟. 露天矿边坡工程[M]. 北京:科学出版社,2016:482–492.(WANG Jiachen,SUN Shuwei. Open pit slope engineering[M]. Beijing:Science Press,2016:482–492.(in Chinese))
[2] 王运敏,项宏海. 排土场稳定性及灾害防治[M]. 北京:冶金工业出版社,2011:1–23.(WANG Yunmin,XIANG Honghai. Stability and disaster prevention of waste dump[M]. Beijing:Metallurgical Industry Press,2011:1–23.(in Chinese))
[3] 孙世国,杨 宏. 典型排土场边坡稳定性控制技术[M]. 北京:冶金工业出版社,2011:1–10.(SUN Shiguo,YANG Hong. Stability control technology of typical dump slope[M]. Beijing:Metallurgical Industry Press,2011:1–10.(in Chinese))
[4] SUN S W,PANG B,HU J B,et al. Characteristics and mechanism of a landslide at Anqian iron mine,China[J]. Landslides,2021,18(7):2 593–2 607.
[5] BISHOP A W. The stability of tips and spoil heaps[J]. Quarterly Journal of Engineering Geology,1973,6(3):1 851–1 861.
[6] MERRY S M,KAVAZABJIAN E,FRITZ W U. Reconnaissance of the July 10,2000,Payatas landfill failure[J]. Journal of Performance of Constructed Facilities,2015,19(2):100–107.
[7] LAVIGNE F,WASSMER P,GOMEZ C. The 21 February 2005,catastrophic waste avalanche at Leuwigajah dumpsite,Bandung,Indonesia[J]. Geoenvironmental Disasters,2014,(1):1–12.
[8] 郭瑞峰,张德胜,薄建芬. 尖山铁矿大型排土场综合治理实践[J]. 山西冶金,2018,41(5):148–149.(GUO Ruifeng,ZHANG Desheng,BO Jianfen. Comprehensive treatment practice of large scale dump in Jianshan iron mine[J]. Shanxi Metallurgy,2018,41(5):148–149.(in Chinese))
[9] ZHAN L T,ZHANG Z,CHEN Y M,et al. The 2015 Shenzhen catastrophic landslide in a construction waste dump:Reconstitution of dump structure and failure mechanisms via geotechnical investigations[J]. Engineering Geology,2018,238:15–26.
[10] RAI R,KHANDELWAL M,JAISWA A. Application of geogrids in waste dump stability:a numerical modeling approach[J]. Environmental Earth Sciences,2012,66(5):1 459–1 465.
[11] 中华人民共和国国家标准编写组. GB 50290—2014 土工合成材料应用技术规范[S]. 北京:中国计划出版社,2014.(The National Standards Compilation Group of People?s Republic of China. GB 50290—2014 Technical code for application of geosynthetics[S]. Beijing:China Plan Press,2014.(in Chinese))
[12] CHEN S C,CHANG K T,WANG S H,et al. The efficiency of artificial materials used for erosion control on steep slopes[J]. Environmental Earth Sciences,2011,62(1):197–206.
[13] CHUNG W,CASCANTE G. Experimental and numerical study of soil-reinforcement effects on the low-strain stiffness and bearing capacity of shallow foundations[J]. Geotechnical and Geological Engineering,2007,25(3):265–281.
[14] RAJESH S,VISWANADHAM B. Hydro-mechanical behavior of geogrid reinforced soil barriers of landfill cover systems[J]. Geotextiles and Geomembranes,2011,29(1):51–64.
[15] ABDESSSEMED M,KENAI S,BALI A. Experimental and numerical analysis of the behavior of an airport pavement reinforced by geogrids[J]. Construction and Building Materials,2015,94:547–554.
[16] WANG Y K,SUN S W,LIU L. Mechanism,Stability and remediation of a large scale external waste dump in China[J]. Geotechnical and Geological Engineering,2019,37(6):5 147–5 166.
[17] 王玉凯,孙书伟,庞 博,等. 露天矿软弱基底排土场卸荷变形机制试验研究[J]. 岩石力学与工程学报,2020,39(2):359–373.(WANG Yukai,SUN Shuwei,PANG Bo,et al. Experimental study on unloading deformation mechanisms of soft base dumps of open-pit mines[J]. Chinese Journal of Rock Mechanics and Engineering,2020,39(2):359–373.(in Chinese))
[18] WANG Y K,SUN S W,PANG B,et al. Base friction test on unloading deformation mechanism of soft foundation waste dump under gravity[J]. Measurement,2020,163:108054.
[19] 孙书伟,庞 博,刘 流. 露天排土场不同排土工艺失稳机制对比试验研究[J]. 岩石力学与工程学报,2021,40(8):1 713–1 726.(SUN Shuwei,PANG Bo,LIU Liu. Comparative tests on failure mechanisms of waste dumps of open-pit mines with different dumping methods[J]. Chinese Journal of Rock Mechanics and Engineering,2021,40(8):1 713–1 726.(in Chinese))
[20] BRAY J W,GOODMAN R E. The theory of base friction models[J]. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts,1981,18(6):453–468.
[21] 中华人民共和国国家标准编写组. GB 51016—2014 非煤露天矿边坡工程技术规范[S]. 北京:中国计划出版社,2014.(The National Standards Compilation Group of People?s Republic of China. GB 51016—2014 Technical code for non-coal open-pit mine slope engineering[S]. Beijing:China Plan Press,2014.(in Chinese))
[22] 中华人民共和国国家标准编写组. GB 51119—2015 冶金矿山排土场设计规范[S]. 北京:中国计划出版社,2015.(The National Standards Compilation Group of People?s Republic of China. GB 51119—2015 Code for waste dump design of metal mine[S]. Beijing:China Plan Press,2015.(in Chinese))
[23] MUMTAZ K. Applied elasticity and plasticity[M]. [S. l.]:Taylor and Francis Group,2018:70–74.
[24] 孙书伟,陈 冲,丁 辉,等. 微型桩群加固土坡稳定性分析[J]. 岩土工程学报,2014,36(12):2 306–2 314.(SUN Shuwei,CHEN Chong,DING Hui,et al. Stability analysis of earth slopes reinforced with micropiles[J]. Chinese Journal of Geotechnical Engineering,2014,36(12):2 306–2 314.(in Chinese))
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