泥石流源区植物根系固土力学机理研究
文献类型:学位论文
作者 | 陆桂红 |
学位类别 | 硕士 |
答辩日期 | 2014 |
授予单位 | 中国科学院研究生院 |
授予地点 | 北京 |
导师 | 欧国强 |
关键词 | 典型植物 抗拉强度 摩擦系数 抗剪强度 固土机理 |
其他题名 | The Mechanism of Roots Reinforcement on Soil in Debris Flow Triggering Area |
学位专业 | 岩土工程 |
中文摘要 | 论文以5.12汶川地震极重灾区-都江堰市虹口乡锅圈岩泥石流沟的物源区作为研究靶区,通过野外调查、室内试验、理论分析,对泥石流源区典型草本植物根系的固土机理进行了深入的研究。 主要结论如下: (1)通过野外调查和重要值计算,确定锅圈岩泥石流源区典型植物为寒芒、节节草、小飞蓬、铁杆蒿等乡土植物。 (2)锅圈岩泥石流源区典型草本植物根系的抗极限抗拉力、抗拉强度与根径密切相关,可用幂函数表示;草本植物根系的抗拉强度并不低于乔灌木,在灾区生态恢复时可以考虑应用先锋草本植物。 (3)自主研制改装摩擦试验仪器,开展了根土间摩擦试验,发现根土间摩擦系数随着等效土深的增大逐渐降低,与含水率呈负相关关系,可以用对数函数式表示;另外,直剪试验结果表明,根系对土体内摩擦角的影响较小,对粘聚力的影响较大。 (4)在抗拉、摩擦、抗剪机理分析的基础上,建立了泥石流源区植物根系固土模型,并结合试验数据对模型进行了修正。 |
英文摘要 | Taking Guojuanyan debris flow triggering area as study area, it is typical and representative. It located in Hongkou town, Dujiangyan City where is heavily stricken by 5.12 Wenchuan Earthquake. By quadrat method, theoretical analysis, and a lot of tests, the mechanism of roots reinforcement on soil was deeply researched. The main conclusions are as follows: 1. Guojuanyan debris flow triggering area was mainly distributed with herbs. The top-ranking six typical species of importance value were Miscanthus floridulu, Commelina diffusa, Conyza Canadensis, Artemisia sacrorum, Poa pratensis, Long Kumai. 2. The six typical plant roots’ ultimate tensile force and strength presented power function with root diameter and had good correlation. The herb root tensile strength was not less than trees and shrubs, and ecological restoration in the disaster area can give priority to herb applications. 3. After independently developed and modified friction test instrument, a lot of friction tests between soil and root were carried out. There was a negative correlation between equivalent soil depth, soil moisture content and peak friction coefficient, and they were fitting a logarithmic funcion type. The direct shear test results showed that plant roots had greater impact on soil cohesion than internal friction. 4. Based on the analysis of roots tensile, friction and shear mechanism, this paper established a model of roots reinforcement on soil. In addition, by verifying the experimental data, this model was modified. |
语种 | 中文 |
源URL | [http://ir.imde.ac.cn/handle/131551/8016] ![]() |
专题 | 成都山地灾害与环境研究所_山地灾害与地表过程重点实验室 |
推荐引用方式 GB/T 7714 | 陆桂红. 泥石流源区植物根系固土力学机理研究[D]. 北京. 中国科学院研究生院. 2014. |
入库方式: OAI收割
来源:成都山地灾害与环境研究所
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