非饱和红黏土土水特性及强度特征研究
doi: 10.3969/j.issn.0258-2724.2014.03.004
Soil-Water and Shear Strength Characteristics of Unsaturated Red Clay
-
摘要: 为研究红黏土土体非饱和特性,分别针对典型的原状和重塑红黏土,结合Geo-experts自平衡型压力板仪和ZJ型应变控制式直剪仪开展了不同干密度下土样的非饱和土水特征试验和直剪试验,探讨了红黏土的一些典型非饱和物理力学特征.研究结果表明:矿物赋存状态的改变和微结构的变化是导致红黏土重塑前后物理力学性质发生显著改变的重要因素;原状非饱和红黏土土水曲线呈现典型的三阶段型变化特征,具有较为明显的进气值和残余含水量,而重塑的非饱和红黏土则呈现半抛物线型变化特征;对于原状红黏土来说,非饱和土体黏聚力最大值出现在低含水率状态,对应的含水率比土水曲线的残余含水率高5%~10%.因此,在开展非饱和红黏土抗剪强度试验时,在相应含水率区间处适当增加试验组数可优化试验成果,对于重塑红黏土来说,可根据塑限含水率判断重塑红黏土内摩擦角开始显著减小的区间.Abstract: In order to study the unsaturated characteristics of red clay, Geo-experts self-balanced pressure plate meter and ZJ direct shear apparatus were used in experiments to investigate the soil-water and shear strength characteristics of the typical undisturbed and remolded red clays under different dry densities. Based on the experimental results, the physical and mechanical features of unsaturated red clay were discussed. The results show that mineral composition and micro-structural changes may be the major factors accounting for the difference between physical and mechanical properties of the undisturbed and remolded red clay. The soil-water characteristics curve of undisturbed unsaturated red clay show three stages, which has the obvious air-entry values and residual moisture content, while the soil-water characteristics curve of remodeled unsaturated clay presents a semi-parabolic variation. For the undisturbed red clay, the maximum cohesion occurs in a low moisture condition, and the corresponding moisture content is about 5% to 10% larger than the residual moisture content. Thus, in this case, increasing the number of test groups can optimize the test results. For the remolded red clay, the range of the significantly reduced internal friction angle can be determined according to the plastic limit.
-
MOCARI E J, HOYOS L R, AIDUINO P. Constitutive modeling of unsaturated soil behavior under axisymmetric stress states using a stess/suction-controlled cubieal test cell[J]. International Journal of Plasticity, 2003, 19(1): 1481-1515. MADU R M. An investigation into the geotechnical and engineering properties of some laterites of eastern Nigeria[J]. Engineering Geology, 1977, 11(1): 101-125. GIDIGASO M D. Mode of formation and geotechnical characteristics of laterite materials of Ghanan in relation to soil forming factors[J]. Engineering Geology, 1972, 6(2): 79-150. ABIOLA S A. Mineralogical properties of some nigerian resiual Soil in relation with building problems[J].Engineering Geology, 1980, 15(1/2): 1-13. 刘艳敏. 巴东组软岩残坡积非饱和红粘土土水特征研究[D]. 武汉:中国地质大学, 2011. 伊盼盼, 牛圣宽, 韦昌富. 干密度和初始含水率对非饱和重塑粉土土水特征曲线的影响[J]. 水文地质工程地质, 2012, 39(1): 42-46. YI Panpan, NIU Shengkuan, WEI Changfu. Effect of dry density and initial moisture content on soil water characteristic curve of remolded unsaturated silt[J]. Hydrogeology & Engineering Geology, 2012, 39(1): 42-46. 唐军, 余沛, 颜荣涛, 等. 毕威高速公路玄武岩红土土水特征曲线测定与模型应用研究[J]. 路基工程, 2011(5): 66-72. TANG Jun, YU Pei, YAN Rongtao, et al. Determination of soil-water characteristic curve and model research of basalt laterite in Bijie-Weining Highway[J]. Subgrade Engineering, 2011(5): 66-72. 谈云志. 非饱和红粘土三轴试验研究[J]. 合肥工业大学学报:自然科学版, 2009, 32(5): 725-729. TAN Yunzhi. Study on the triaxial tests of unsaturated lateritic soil[J]. Journal of Hefei University of Technology: Natural Science, 2009, 32(5): 725-729. 王中文, 洪宝宁, 刘鑫, 等. 红粘土抗剪强度的水敏性研究[J]. 四川大学学报:工程科学版, 2011, 43(1): 17-22. WANG Zhongwen, HONG Baoning, LIU Xin, et al. Water-sensitive properties of shear strength of red clay[J]. Journal of Sichuan University: Engingeering Science Edition, 2011, 43(1): 17-22. 赵颖文, 孔令伟, 郭爱国. 广西原状红粘土力学性状与水敏性特性[J]. 岩土力学, 2003, 24(4): 568-572. ZHAO Yingwen, KONG Lingwei, GUO Aiguo. Mechanical behaviors and water-sensitive properties of intact Guangxi laterite[J]. Rock and Soil Mechanics, 2003, 24(4): 568-572. 汤康民. 红粘土动力性质的研究[J]. 西南交通大学学报, 1993, 92(4): 72-77. TANG Kangmin. Experimental investigation on the dynamic properties of red clay[J]. Journal of Southwest Jiaotong University, 1993, 92(4): 72-77. 中华人民共和国建设部. JGJ89-92原状土取样技术标准[S]. 北京:中国建筑工业出版社, 1989. 罗书学, 李龙起, 徐骏, 等. 高陡边坡运营安全防灾监控及报警系统技术研究科研报告. 成都:西南交通大学岩土工程系, 2012. 刘小文, 常立君, 胡小荣. 非饱和红土基质吸力与含水率及密度关系试验研究[J]. 岩土力学, 2009, 30(11): 3302-3306. LIU Xiaowen, CHANG Lijun, HU Xiaorong. Experimental research of matric suction with water content and dry density of unsaturated laterite[J]. Rock and Soil Mechanics, 2009, 30(11): 3302-3306. 刘小文, 常立君. 非饱和红土强度特性的试验研究[J]. 建筑科学, 2009, 25(1): 70-72. LIU Xiaowen, CHANG Lijun. Experimental study on strength of unsaturated laterite[J]. Building Science, 2009, 25(1): 70-72. GEO-Experts Company. GEO-Experts soil-water characteristic curve device reference manual[M]. New York: Routledge, 2009: 36-98. PHAM Q H. A volume-mass constitutive model for unsaturated soils.: Department of Civil Engineering, University of Saskatehewan, 2005: 86-89. 中华人民共和国建设部. GB/T50123-1999土工试验方法标准[S]. 北京:中国计划出版社, 1999. LU Ning, LIKOS W J. Unsaturated soil mechanics[M]. Hoboken:John Wiley&Sons, Inc., 2005: 134-154. ELOUSSAIEF M, JARRAYA I, BENZINA M. Adsorption of copper ions on two clays from Tunisia: pH and temperature effects[J]. Applied Clay Science, 2009, 46(1): 409-413. 李景阳, 朱立军, 梁风, 等. 碳酸盐岩残积红粘土微观结构的扫描电镜研究[J]. 中国岩溶, 2002, 21(4): 233-312. LI Jingyang, ZHU Lijun, LIANG Feng, et al. Study with scanning electron microscope on micro-texture of the residual red clay from carbonate rocks[J]. Carsologica Sinica, 2002, 21(4): 233-312.
点击查看大图
计量
- 文章访问数: 1013
- HTML全文浏览量: 65
- PDF下载量: 533
- 被引次数: 0