摘要
通过对膨胀土样进行不同次数的无约束干湿循环,得到了不同裂隙开展程度的膨胀土样,对不同裂隙开展程度的膨胀土饱和试样进行了直剪试验,并首次进行了三轴试验,研究了膨胀土饱和强度随裂隙开展而变化的规律。试验结果表明,膨胀土饱和强度随干湿循环次数呈双曲线关系衰减。对不同裂隙开展程度的膨胀土试样进行拍照,反映了试样裂隙的开展过程,结合直剪试验和三轴试验结果说明,正是裂隙的开展使得膨胀土强度降低。通过对试验结果的分析,指出膨胀土强度指标的选取应考虑裂隙开展的影响,并给出了选取标准。
Based on the unrestraint wet-dry cycles of different numbers made on the expansive soil samples, the saturated samples with various cracking scales are obtained, and then direct shear tests are made on them. Moreover, the law of the variation of the saturated strength of the samples along with the crack evolution is initially studied with the triaxial test concerned ; from which result shows that the saturated strength of the expansive soil presents a hyperbolic declination along with numbers of the wet-dry cycles. The various crack evolutions of the samples are imaged with photos made on them. On the bases of both the direct shear test and the triaxial test, it is explained that the strength declination is just due to the development of the cracking. Through the analysis on the test result, it is pointed out that the influence of the cracking development must be considered during the selection of the strength index for the expansive soil and the relevant selection standard must be given as well.
出处
《水利水电技术》
CSCD
北大核心
2010年第9期100-104,共5页
Water Resources and Hydropower Engineering
基金
"十一五"国家科技支撑计划重大项目(2006BAB04A10)
关键词
膨胀土
裂隙
干湿循环
残余强度
expansive soil
crack
wet-dry cycle
residual strength
