土壤剪切力影响因素研究.docVIP

目录 摘 要 I 关键词 II Abstract II Keywords III 1 前言 1 2 材料与方法 4 2.1 土壤的采集 4 2.2 直剪仪构造及其原理 5 2.3实验步骤及测定方法 6 3 实验数据处理与分析 7 3.1原状土与重塑土剪切比较 8 3.1.1 剪切曲线差异 8 3.1.2 影响抗剪强度的因素 14 3.2 原状土与重塑土的线性拟合 17 3.2.1 散点图 17 3.2.2 拟合曲线 19 4 结果与讨论 19 21 6 致谢 23 摘 要 从土壤力学上看, 土壤水蚀是雨滴对土粒的溅击剪切作用和径流对土粒的冲刷剪切作用的过程综合,所以土壤的抗剪强度是区域水土流失评价中反映土壤力学特性的重要指标；为了从土壤力学方面探索防治水土流失的途径与措施, 该文采用直剪仪对临沂地区山5 种典型植被的原状土和重塑土抗剪强度进行试验测定。通过比较相同植被同干密度、同含水率的原状土与重塑土在同一垂直荷载下的剪切差异,以期得到从较易获得的重塑土抗剪强度到原状土的回归模型，并研究影响土壤抗剪强度的土壤属性因素。研究结果表明: 原状土剪切位移小于重塑土; 在相同垂直荷载作用下, 同一植被原状土的抗剪强度大于与其同干密度、同含水率的重塑土。原状土的剪切破坏近似于塑性破坏, 而重塑土则属于弹性破坏; 原状土的抗剪强度并以此建立关于原状土的抗剪强度回归模型；垂直荷载、土壤干密度、土壤含水率影响土壤的抗剪强度，可以建立相应的回归模型。 关键词 ：抗剪强度；干密度；原状土；重塑土；含水率；回归模型 Abstract From the view of soil mechanics, soil erosion is the process of raindrops on the soil particle splash shearing action and runoff shear effect on soil particle synthesis, so the soil shear strength is one of the important indexes to reflect the characteristics of soil mechanics in assessment of regional soil and water loss；In order to explore the ways and measures of preventing and controlling soil and water loss from soil mechanics, this paper adopts the undisturbed soil direct shear apparatus for 5 kinds of typical vegetation in Linyi mountain and remolded soil shear strength test。Through the comparison of the same vegetation with the stem of undisturbed soil and remolded soil density, the water content in the same vertical load shear difference,in order to get more easily remolded soil obtained from the shear strength of undisturbed soil to the regression model, and the influence of soil properties on shear strength of soil factors and the influence of soil properties on shear strength of soil factors. The results show that:undisturbed soil shear displacement than remolded soil;Under the same vertical load, the same vegetation intact soil shear strength is greater than the same dry density, remolded soil with water content.Shear failure of the undisturbed soil is similar to plastic failure, a