Li Tao, Lyu Chunjuan, Jiang Chenggang, et al. Effects of Water Content and Polyacrylamide Molecular Weight on Shear Strength of Reconstructed Iron Tailing Sand[J]. Bulletin of Soiland Water Conservation, 2022, 42(2): 89-97.
DOI:
Li Tao, Lyu Chunjuan, Jiang Chenggang, et al. Effects of Water Content and Polyacrylamide Molecular Weight on Shear Strength of Reconstructed Iron Tailing Sand[J]. Bulletin of Soiland Water Conservation, 2022, 42(2): 89-97. DOI: 10.13961/j.cnki.stbctb.2022.02.013.
Effects of Water Content and Polyacrylamide Molecular Weight on Shear Strength of Reconstructed Iron Tailing Sand
[Objective] The effects of water content and molecular weight of polyacrylamide (PAM) on shear strength of reconstructed iron tailing sand were analyzed in order to better understand slope stability and ecological restoration of mining areas. [Methods] An indoor shear strength experiment was conducted by reconstructing iron tailing sand. Five reconstruction soil mixing rate treatments of soil (S) and tailings (T) were established: S (0% T)
S3T1 (25% T)
S1T1 (50% T)
S1T3 (75% T) and T (100% T). Treatments also included two water contents (15%
20%)
two molecular weights of PAM (3.00×106
6.00×106 Da)
and three compaction states (loose
tight
and dense) for each reconstruction pattern. [Results] ① Under the same compaction state
the internal friction angle
cohesion
and shear strength for the five reconstruction patterns all decreased with increasing water content. ② Under the same water content
the internal friction angle
cohesion
and shear strength of the five reconstruction patterns increased with increasing compaction. ③ Addition of PAM effectively improved the shear strength of reconstructed iron tailing sand
and shear strength decreased with increasing molecular weight of PAM. ④ When PAM with a molecular weight of 3.00×106 Da was added into the five reconstruction patterns
the shear strength and water infiltration capacity of S3T1 were greater than for the other reconstruction patterns. [Conclusion] The reconstruction pattern of S3T1 with a water content of 15% and PAM molecular weight of 3.00×106 Da were conducive to the restoration of the ecological environment in mining areas and to the improvement of the stability of iron tailing sand.
Al-Abed N, Amayreh J, Shudifat E, et al. Polyacrylamide(PAM) effect on irrigation induced soil erosion and infiltration [J]. Archives of Agronomy and Soil Science, 2003,49(3):301-308.
Sepaskhah A R, Shahabizad V. Effects of water quality and PAM application rate on the control of soil erosion, water infiltration and runoff for different soil textures measured in a rainfall simulator [J]. Biosystems Engineering, 2010,106(4):513-520.
Sun Bo, Lyu Chunjuan, Bi Rutian, et al. Effects of polyacrylamide molecular weight and mass concentration on water transport characteristics of iron tailings [J]. Scientific Reports, 2021,11(1):1-15.
Lu Shaoyong, Chen Fangxin, Huu Hao Ngo, et al. Effect of straw and polyacrylamide on the stability of land/water ecotone soil and the field implementation [J]. Ecological Engineering, 2016,94:12-21.
Chen Zhang, Chen Wenlu, Li Chengjun, et al. Effects of polyacrylamide on soil erosion and nutrient losses from substrate material in steep rocky slope stabilization projects [J]. Science of the Total Environment, 2016,54(6):26-33.
Hu Xia, Liu Lianyou, Li Shunjiang, et al. Development of soil crusts under simulated rainfall and crust formation on a loess soil as influenced by polyacrylamide [J]. Pedosphere, 2012,22(3):415-424.