Influence Factors of Root-Soil Composite Slope Stability during Spring Thawing

ZHANG Xiao-rong; MA Yan-xia; ZHANG Wu-yu

doi:10.11988/ckyyb.20220653

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Journal of Changjiang River Scientific Research Institute ›› 2023, Vol. 40 ›› Issue (11) : 154-159. DOI: 10.11988/ckyyb.20220653

Rock-Soil Engineering

Influence Factors of Root-Soil Composite Slope Stability during Spring Thawing

ZHANG Xiao-rong^1,2, MA Yan-xia^1,2, ZHANG Wu-yu^1,2

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Abstract

In spring thawing period, slopes in seasonal frozen zone is susceptible to shallow slide due to thermal thawing. To investigate the stability of ecological slopes during this period, laboratory direct shear tests were conducted on the freeze-thaw interfaces of plain soil and root-soil composites. The root system was simplified as taproot type. The variation in shear strength indices of both soils was compared and analyzed. Through numerical simulation, the shear failure in the plastic zone of samples in the presence or in the absence of freeze-thaw interface was analyzed, and a model was developed to calculate the safety factor of slope stability when plant roots penetrate the freeze-thaw interface. Results indicate that as freeze-thaw cycles increase, the damage to the shear strength of plain soil at the freeze-thaw interface is greater than that of root-soil composite. Additionally, the cohesion of soil at the interface decreases, while friction angle increases for both plain soil and root-soil composite. The shear plastic zone of samples with freeze-thaw interface primarily develops within the soil body in the normal thawing zone and exhibits a significantly larger volume compared to samples with no freeze-thaw interface. By passing through the freeze-thaw interface, roots significantly raise the shear strength of the soil, thus enhancing the slope stability in spring thawing period. These findings provide a scientific foundation for the design, construction, and maintenance of ecological slope projects in seasonal frozen regions.

Key words

root-soil composite / freeze-thaw cycle / freeze-thaw interface / direct shear test / slope stability

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ZHANG Xiao-rong, MA Yan-xia, ZHANG Wu-yu. Influence Factors of Root-Soil Composite Slope Stability during Spring Thawing[J]. Journal of Changjiang River Scientific Research Institute. 2023, 40(11): 154-159 https://doi.org/10.11988/ckyyb.20220653

References

[1] 葛琪, 李京子, 武鹤, 等. 基于有限差分法的季冻区公路土质路堑边坡稳定性分析[J]. 黑龙江工程学院学报, 2017, 31(1): 12-14, 18.
[2] 靳德武, 牛富俊, 李宁. 青藏高原多年冻土区斜坡稳定性研究进展[J]. 水文地质工程地质, 2006, 33(4): 98-102.
[3] 武鹤, 刘莹莹, 葛琪. 土质路堑边坡冻融浅层的滑塌机理与数值模拟[J]. 黑龙江科技大学学报, 2017, 27(5): 503-507.
[4] 程永春, 葛琪, 何锋. 季冻区土质边坡滑动界面临界深度的试验研究[J]. 岩土力学, 2010, 31(4): 1042-1046.
[5] 邓爱平. 基于冻融界面对路基土体抗剪强度的影响研究[J]. 湖南交通科技, 2017, 43(3): 91-93.
[6] 葛琪, 李京子, 武鹤, 等. 寒区公路土质边坡冻融界面的抗剪强度试验[J]. 交通科技与经济, 2017, 19(1): 39-41, 45.
[7] 汪恩良, 肖尧, 许春光, 等. 封闭条件下粉质黏土冻融交界面抗剪强度研究[J]. 东北农业大学学报, 2020, 51(3): 61-70.
[8] 王博, 刘志强, 赵晓东, 等. 高压正融土与结构接触面剪切力学特性试验研究[J]. 岩土力学, 2017, 38(12): 3540-3546.
[9] 陈国良,牛富俊,穆彦虎,等.季冻区矿山排土场粗粒土冻融界面剪切性能研究[J].金属矿山,2018(12):150-156.
[10] QU Y L, NI W K, NIU F J, et al. Shear Properties and Mechanism of Freeze-Thaw Interface in Unsaturated Coarse-grained Soil from Qinghai-Tibet Plateau[J]. Advances in Civil Engineering, 2021, 7: 1-12.
[11] BAETS S D,POESEN J,REUBENS B, et al. Root Tensile Strength and Root Distribution of Typical Mediterranean Plant Species and Their Contribution to Soil Shear Strength[J]. Plant & Soil, 2008,305(Supp.1): 207-226.
[12] 黄钢, 郑明新, 王庆, 等. 考虑降雨入渗条件的植被边坡稳定性评价[J]. 长江科学院院报, 2020, 37(4): 160-167.
[13] 卢海静, 胡夏嵩, 付江涛, 等. 寒旱环境植物根系增强边坡土体抗剪强度的原位剪切试验研究[J]. 岩石力学与工程学报, 2016, 35(8): 1712-1721.
[14] 刘向峰,郝国亮,于冰.露天矿排土场草本植物根系加固效果[J].长江科学院院报,2022,39(5):83-88.
[15] 王恒星, 杨林. 冻融作用下草本植物根系加固土体试验研究[J]. 冰川冻土, 2018, 40(4): 792-801.
[16] 刘红军, 郭颖, 单炜, 等. 土质路堑边坡冻融失稳及植被护坡机理研究[J]. 岩土工程学报, 2011, 33(8): 1197-1203.
[17] WU T H, MCKINNELL III W P, SWANSTON D N. Strength of Tree Roots and Landslides on Prince of Wales Island, Alaska[J]. Canadian Geotechnical Journal, 1979, 16(1): 19-33.
[18] 景常荣. 斜坡稳定性安全系数的统一解[J]. 地下空间与工程学报, 2007, 3(增刊2): 1537-1540.