Abstract:To investigate the crack evolution process—from initiation to propagation and stabilization—in soils with varying organic matter contents at the slopes of open-pit coal mine dump sites, and to assess the influence of organic matter content on soil water stability, this study focuses on the Yimin Open-Pit Coal Mine in the Inner Mongolia Autonomous Region. Considering the effects of drying-wetting and drying-wetting-freezing-thawing cycles, laboratory tests were conducted on soil samples with different organic matter contents. These tests included drying tests, drying-wetting cycles, drying-wetting-freezing-thawing cycles, and disintegration tests. Using image digital processing software (PCAS), we analyzed the crack initiation and development patterns of soil samples under various testing conditions, as well as the impact of organic matter content on water stability. The experimental results indicate that during the drying process, soil samples with higher organic matter content exhibit faster moisture evaporation rates under the same drying duration. As organic matter content increases, the total crack area, total crack length, and average crack width of the soil surface all show an upward trend, with the cracks developing in a more oriented manner. Following drying-wetting cycles, organic matter has an inhibitory effect on soil desiccation cracking, and after four cycles, the crack morphology tends to stabilize. For soil samples subjected to drying-wetting-freezing-thawing cycles, both the organic matter content and the number of cycles promote crack development. As organic matter content and the number of cycles increase, the total crack area, total crack length, and average crack width also increase correspondingly, with the crack morphology of the soil surface becoming essentially stable after three to four drying-wetting-freezing-thawing cycles.
褚 峰1*,罗 旭1,张宏刚2,杨 涛1,王雪艳1,李 者1. 不同路径下有机质对露天煤矿排土场边坡土体干缩开裂演化特征影响研究[J]. 岩石力学与工程学报, 2026, 45(5): 1554-1570.
CHU Feng1*, LUO Xu1, ZHANG Honggang2, YANG Tao1, WANG Xueyan1, LI Zhe1. Effect of organic matter on the evolution behavior of desiccation cracks in dump slope soils of open-pit coal mines. , 2026, 45(5): 1554-1570.
[1] JIE D F,XU X Y,GUO F. The future of coal supply in China based on non-fossil energy development and carbon price strategies[J]. Energy,2021,220:119644.
[2] 谢和平,吴立新,郑德志. 2025年中国能源消费及煤炭需求预测[J]. 煤炭学报,2019,44(7):1 949–1 960.(XIE Heping,WU Lixin,ZHENG Dezhi. Prediction on the energy consumption and coal demand of China 2025[J]. Journal of China Coal Society,2019,44(7):1 949–1 960.(in Chinese))
[3] 田 会,才庆祥,甄 选. 中国露天采煤事业的发展展望[J]. 煤炭工程,2014,46(10):11–14.(TIAN Hui,CAI Qingxiang,ZHEN Xuan. Development prospects of surface coal mining industry in China[J]. Coal Engineering,2014,46(10):11–14.(in Chinese))
[4] 李浩荡,佘长超,周永利,等. 我国露天煤矿开采技术综述及展望[J]. 煤炭科学技术,2019,47(10):24–35.(LI Haodang,SHE Changchao,ZHOU Yongli,et al. Summary and prospect of open-pit coal mining technology in China[J]. Coal Science and Technology,2019,47(10):24–35.(in Chinese))
[5] 孙书伟,胡家冰,刘 流,等. 抚顺西露天矿边坡岩体结构与灾害预报模型研究[J]. 岩石力学与工程学报,2025,44(7):1 695–1 708. (SUN Shuwei,HU Jiabing,LIU Liu,et al. Investigations of the rock mass structure and disaster prediction model of slopes in the Fushun west open pit mine[J]. Chinese Journal of Rock Mechanics and Engineering,2025,44(7):1 695–1 708.(in Chinese))
[6] 王知乐,田 雨,周 伟,等. 壳聚糖联合EICP对露天矿排土场边坡抗侵蚀性影响机制[J]. 煤炭学报,2024,49(12):4 713–4 727. (WANG Zhile,TIAN Yu,ZHOU Wei,et al. Mechanism of the effect of chitosan combined with EICP on the erosion resistance of slopes in open-pit mine dump[J]. Journal of China Coal Society,2024,49(12):4 713–4 727.(in Chinese))
[7] 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.
[8] 孙书伟,刘 流,郑明新,等. 抚顺西露天矿区边坡灾害多源监测预警系统及工程应用[J]. 岩石力学与工程学报,2024,43(5):1 124–1 138.(SUN Shuwei,LIU Liu,ZHENG Mingxin,et al. Slope disaster monitoring and early warning system in Fushun west open pit mine and its engineering application[J]. Chinese Journal of Rock Mechanics and Engineering,2024,43(5):1 124–1 138.(in Chinese))
[9] 李 晓,张年学,盛祝平,等. 武隆鸡尾山滑坡发生机制与裂缝成因分析[J]. 岩石力学与工程学报,2020,39(1):1–12.(LI Xiao,ZHANG Nianxue,SHENG Zhuping,et al. Sliding mechanisms and fracture genesis of Jiweishan landslide in Wulong[J]. Chinese Journal of Rock Mechanics and Engineering,2020,39(1):1–12.(in Chinese))
[10] 张金贵. 露天煤矿工作帮边坡破坏模式及稳定性控制研究[J]. 煤炭工程,2019,51(9):132–135.(ZHANG Jingui. Study on failure mode and stability control of working[J]. Coal Engineering,2019,51(9):132–135.(in Chinese))
[11] 桂 跃,付 坚,吴承坤,等. 高原湖相泥炭土渗透特性研究及机制分析[J]. 岩土力学,2016,37(11):3 197–3 207.(GUI Yue,FU Jian,WU Chengkun,et al. Hydraulic conductivity of lacustrine peaty soil in plateau areas and its mechanism analysis[J]. Rock and Soil Mechanics,2016,37(11):3 197–3 207.(in Chinese))
[12] THI D V,AMADE P,SAHAR H,et al. Modelling desiccation crack geometry evolution in clayey soils by analytical and numerical approaches[J]. Canadian Geotechnical Journal,2019,56(5):720–729.
[13] WEI Y,TANG C S,LU Y,et al. Evaporation and desiccation cracking of soils:Experiment evidence and insight on the freeze-thaw cycle dependence[J]. Engineering Geology,2024,329:107399.
[14] TANG C S,ZHU C,LENG T,et al. Three-dimensional characterization of desiccation cracking behavior of compacted clayey soil using X-ray computed tomography[J]. Engineering Geology,2019,255:1–10.
[15] CHENG Q,TANG C S,ZENG H,et al. Effects of microstructure on desiccation cracking of a compacted soil[J]. Engineering Geology,2020,265:105418.
[16] CAI Z L,TANG C S,CHENG Q,et al. Fracture morphology of desiccation cracks in clayey soil[J]. Canadian Geotechnical Journal,2024,61(9):1 955–1 967.
[17] WANG L L,TANG C S,SHIN B,et al. Nucleation and propagation mechanisms of soil desiccation cracks[J]. Engineering Geology,2018,238:27–35.
[18] ZHOU Z H,XUE Q. Investigation of cracking behavior of fine- grained clays exposed to different humidity environments and engineering implications based on X-ray computed tomography[J]. Construction and Building Materials,2024,450:138643.
[19] WANG T,TANG C S,LIU W J,et al. Insight into the initiation and propagation mechanism of desiccation cracking in clayey soil from DEM simulations[J]. Computers and Geotechnics,2024,175:106694.
[20] TANG C S,ZHU C,CHENG Q,et al. Desiccation cracking of soils:A review of investigation approaches,underlying mechanisms,and influencing factors[J]. Earth-Science Reviews,2021,216:103586.
[21] ZHANG J M,LUO Y,ZHOU Z,et al. Effects of preferential flow induced by desiccation cracks on slope stability[J]. Engineering Geology,2021,288:106164.
[22] SAYAKO H,KENJI O. Modeling and simulating methods for the desiccation cracking[J]. International Journal of Computational Engineering and Science,2018,15(1):1840011.
[23] 黄昌勇. 土壤学[M]. 北京:中国农业出版社,2000:35–39. (HUANG Changyong. Soil science[M]. Beijing:Chinese Agriculture Press,2000:35–39.(in Chinese))
[24] FAWZI H,RACHID Z. Effects of organic matter on physical properties of dredged marine sediments[J]. Waste and Biomass Valorization,2018,8(18):543–556.
[25] 裴利华,杨醒宇,桂 跃,等. 有机质含量及组分对泥炭土物理力学性质影响[J]. 水文地质工程地质,2022,49(2):77–85.(PEI Lihua,YANG Xingyu,GUI Yue,et al. Effect of organic matter content and composition on physical and mechanical properties of peat soil[J]. Hydrogeology Engineering Geology,2022,49(2):77–85.(in Chinese))
[26] 吕 岩,佴 磊,徐 燕,等. 有机质对草炭土物理力学性质影响的机制分析[J]. 岩土工程学报,2011,33(4):655–660.(LV Yan,NIE Lei,XU Yan,et al. The mechanism of organic matter effect on physical and mechanical properties of turfy soil[J]. Chinese Journal of Geotechnical Engineering,2011,33(4):655–660.(in Chinese))
[27] 蔡华军,华 伦,徐其富,等. 考虑有机质赋存形态的含有机质土一维压缩与渗透特性研究[J]. 土木工程学报,2024,57(11):33–44.(CAI Huajun,HUA Lun,XU Qifu,et al. One-dimensional compression and permeability characteristics of organic soil considering the occurrence of organic matter[J]. China Civil Engineering Journal,2024,57(11):33–44.(in Chinese))
[28] 褚 峰,罗 旭,张宏刚,等. 有机质对露天煤矿排土场基底土体力学及渗透性能影响试验研究[J]. 岩石力学与工程学报,2025,44(3):752–768.(CHU Feng,LUO Xu,ZHANG Honggang,et al. Experimental study on the influence of organic matter on the soil mechanics and permeability of the base soil of open-pit coal mine[J]. Chinese Journal of Rock Mechanics and Engineering,2025,44(3):752–768.(in Chinese))
[29] WEI Y,TANG C S,LU Y,et al. Evaporation and desiccation cracking of soils:Experiment evidence and insight on the freeze-thaw cycle dependence[J]. Engineering Geology,2024,329:107399.
[30] KONG F S,YAN X,ZHONG J H,et al. Disintegration characteristics of sodic-saline loessial soil after freeze-thaw and wet-dry cycles[J]. Earth Surface Processes and Landforms,2024,49:2 229–2 244.
[31] 桂 跃,刘 锐,赵振兴,等. 高分解度泥炭土–土水特征曲线研究[J]. 防灾减灾工程学报,2021,41(3):622–628.(GUI Yue,LIU Rui,ZHAO Zhenxing,et al. Study on soil water characteristic curve of peaty soil with high degree of decomposition[J]. Journal of Disaster Prevention and Mitigation Engineering,2021,41(3):622–628.(in Chinese))