| 容县压实花岗岩残积土的力学性质与微结构特性研究 |
| |
| 引用本文： | 王志兵,麦棠坤,齐程.容县压实花岗岩残积土的力学性质与微结构特性研究[J].水文地质工程地质,2018,0(5):101-101. |
| |
| 作者姓名： | 王志兵 麦棠坤 齐程 |
| |
| 作者单位： | 1.广西岩土力学与工程重点实验室，广西 桂林541004; 2.桂林理工大学土木与建筑工程学院，广西 桂林541004 |
| |
| 基金项目： | 国家自然科学基金项目资助（41302227）；广西自然科学基金项目资助（2017GXNSFAA198092） |
| |
| 摘 要： | 选取广西容县花岗岩残积土为研究对象，取击实曲线上3个不同含水率对应的压实样（最佳含水率及干侧、湿侧，后两者对应的干密度相同）分别进行了直剪试验、扫描电镜观测（SEM）和压汞试验（MIP），并从微观特征解释其力学性能的差异。结果表明:（1）花岗岩残积土在3种压实状态下具有相同应力-应变曲线形状，无明显峰值，抗剪强度在最佳状态时的最高，湿侧状态抗剪强度与干侧状态相近，3种状态下内摩擦角值差别较小，但黏聚力在最佳状态时最大，干侧和湿侧状态较最佳状态分别下降66.4%和43.1%；（2）花岗岩残积土在湿侧状态下普遍形成团聚体，团聚体之间呈架空结构，累积孔隙体积最大，为明显的双峰分布孔隙特征；在最佳状态下组构最密，高岭石片定向性排列；在干侧状态下高岭石片呈片架结构，累积孔隙体积最小；随着含水率的降低，土样双峰孔隙特征逐渐变得不明显；（3）花岗岩残积土在不同状态时的微观特性较好地解释其力学性质的差异。
|
| 关 键 词： | 花岗岩残积土 最佳含水率 抗剪强度 微观结构 压汞试验 |
| 收稿时间： | 2018-02-05 |
| 修稿时间： | 2018-03-20 |
Shear strength and microstructure of compacted granite residual soils in Rong County |
| |
| WANG Zhibing,MAI Tangkun,QI Cheng.Shear strength and microstructure of compacted granite residual soils in Rong County[J].Hydrogeology and Engineering Geology,2018,0(5):101-101. |
| |
| Authors: | WANG Zhibing MAI Tangkun QI Cheng |
| |
| Affiliation: | 1.State Key Laboratory of Geomechanics and Geotechnical Engineering, Guilin,Guangxi541004, China; 2.College of Civil Engineering and Architecture, Guilin University of Technology, Guilin, Guangxi541004, China |
| |
| Abstract: | Granite residual soil is abundant in the humid tropics of southern China. It has extensively been used as fill materials in various applications, such as back-filling materials for pavements. Some subgrade diseases are related to the compaction degree and the moisture content of the compacted granite residual soil. On the basis of analyses of the characteristics of the granite residual soil in Rong County Guangxi, a series of direct shear tests are carried out on the compacted samples with three moisture contents (optimum moisture content of the standard compaction test, on the wet side of the optimum moisture content, and on the dry side). The microstructure and fabric characteristics of these compacted samples are analyzed by scanning electron microscope and mercury intrusion pore size distribution measurements. The experimental results show that there samples have the same stress-strain curve shapes with no pronounced peaks. The optimum sample has the highest shear strength, the three samples have nearly equal internal friction angle, the optimum sample has the highest cohesion, and the cohesion of the wet sample and the dry sample decreases by 66.4% and 43.1%, respectively. The wet sample has aggregate structure and open structure and exhibits a doublet pore-size distribution with the highest cumulative pore volumes, while the optimum sample has a matrix structure with parallel alignment of mineral grains. The dry sample has a piece of frame structure with the smallest cumulative pore volumes. The microscopic features of these three compacted samples are explained by the difference of the shear strength accurately. |
| |
| Keywords: | |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《水文地质工程地质》浏览原始摘要信息 |
|
点击此处可从《水文地质工程地质》下载全文 |
|
