指数分布型根系根-土复合体强度特性研究  

Study on the strength characteristics of root-soil composite with exponential rooting systems

作　　者：叶天浩 王光进[1,2] 蔡彬婷 李树建 赵雷 李小双[4] Ye Tianhao;Wang Guangjin;Cai Binting;Li Shujian;Zhao Lei;Li Xiaoshuang(Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming Yunnan 650093,China;Yunnan International Technology Transfer Center for Mineral Resources Development and Solid Waste Resource Utilization,Kunming Yunnan 650093,China;Yunnan Phosphate Group Co.,Ltd.,Kunming Yunnan 650600,China;School of Urban Construction,Changzhou University,Changzhou Jiangsu 213100,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]云南省矿产资源开发与固废资源利用国际技术转移中心,云南昆明650093 [3]云南磷化集团有限公司,云南昆明650600 [4]常州大学城市建设学院,江苏常州213100

出　　处：《化工矿物与加工》2023年第5期45-50,共6页Industrial Minerals & Processing

基　　金：国家自然科学基金项目(52174114);云南省矿产资源开发与固废资源利用国际技术转移中心项目(202203AE140012)。

摘　　要：指数分布型是排土场护坡植物根系中十分常见的根型,为进一步揭示根-土复合体固土护坡的内在机理,针对现有数值模拟方法不易还原自然条件下根系真实形态的问题,结合土工试验,优化数值模拟方法,研究了细观尺度下指数分布型根系根-土复合体的力学强度特性,结果表明:根-土复合体试样表现出与素土不同的颗粒位移特征,根系的存在能够显著提高土体的整体性,根的张拉作用限制了土体的侧向变形;构建的根-土复合体离散元模型可以较好地反映含根系土壤的力学效应,根系内部应力主要集中于剪切平面附近的根系部,各垂直荷载下未发现根系整体贯通断裂,断裂整体上呈现出在剪切平面集中、土体内零星分布的特点;素土试样的剪应力-剪切位移曲线呈现出带有波峰的应变软化趋势,而根-土复合体试样呈现出无波峰的应变硬化趋势;草本植物根系主要增大了根-土复合体的黏聚力,对内摩擦角的影响不明显。研究成果对于深入了解根土相互作用加固土壤的机理和推进根-土复合体的数值模拟研究具有重要的参考意义。The exponential rooting is very popular in the root systems with slope covering plants in dump.In order to further study the intrinsic mechanism of soil consolidation and slope protection of its root-soil composite,and to address the problem that the application of existing numerical simulation methods is not likely to restore the real form of root systems under natural conditions,in this paper combining soil tests,optimizing numerical simulation methods,the mechanical strength characteristics of root-soil composites with exponential root systems at the meso scale were studied.The results show that the root-soil composite samples exhibited different particle displacement characteristics from those of the plain soil,the presence of the root system can significantly improve the integrity of the soil,and the root tension limits the lateral deformation of the soil.The discrete element model of root-soil composite was constructed in this paper to better reflect the mechanical effect of soil-containing root system.The internal stress of root system is mainly concentrated in the root part near the shear plane,and no fracture of root system in the overall connection state was found under each vertical load and the fracture area as a whole presents the characteristics of concentration in the shear plane and sporadic distribution within the soil.The stress displacement curve of plain soil sample shows a strain softening trend,while the root-soil composite shows a strain hardening trend without wave crest,the herbaceous plant roots mainly increase the cohesion of root-soil composite,and the effect on the internal friction angle was not obvious.The results of the study are of great reference significance for insight into the mechanism of root-soil interaction for soil consolidation and advancing the numerical simulation study of the root-soil composite.

关 键 词：指数分布型根系 根-土复合体 土工试验 细观尺度 数值模拟 固土护坡 

分 类 号：X171.4[环境科学与工程—环境科学] TD88[矿业工程—矿山开采]