摘要
为研究高填方路堤压实土的蠕变特性,对3种不同压实度(90%,93%,96%)的压实土开展了5种不同竖向荷载(100,200,400,600,800 k Pa)的一维固结蠕变试验.试验结果表明:1)压实土的蠕变变形呈现明显的非线性特征;2)蠕变有效应力越大,蠕变变形越显著;3)压实度越高,蠕变变形的敏感性越差.采用基于分数阶微积分的类Kelvin-Voigt流变模型结合试验数据得到模型参数,分析了模型分数阶阶次β,[H]元件弹性模量E0以及[FC]元件弹性模量E1与土样压实度K的关系,结果表明,随着土样压实度的增大,分数阶阶次β减小,模量E0和E1增大,预测结果与试验数据吻合良好,显示分数阶模型参数能合理地反应土样的流动性.
In order to investigate the creep properties of compacted clay of high- filled embankment,one-dimensional consolidation creep tests were carried out with three different compaction degrees of 90%,93% and96% under five different kinds of vertical loads of 100,200,400,600,800 k Pa,respectively. The results show that: 1) The creep deformation of compacted clay presents obvious nonlinearly characteristic. 2) Creep deformation decreases with the increase of effective stress. 3) The sensitivity of creep deformation decreases with the increase of soil compaction. When the data of experimental results is fitted by similar Kelvin-Voigt rheological model based on fractional calculus, the parameters of this model are obtained. The relationship between fractional order β and compaction degree K,elastic modulus E0 of [H] element and compaction degree K,as well as elastic modulus E1 of [FC] element and compaction degree K were analyzed,respectively. The results show that the fractional order β decreases with the increase of compaction degree of clay,but both of the elastic modules E0 and E1increase. Prediction results are in good agreement with experimental data,and this prove that the parameters of the proposed model based on fractional calculus describe the flow ability of compacted clay reasonably.
出处
《湖南科技大学学报(自然科学版)》
CAS
北大核心
2015年第3期46-51,共6页
Journal of Hunan University of Science And Technology:Natural Science Edition
基金
国家自然科学基金资助项目(51308485)
湖南省自然科学基金资助项目(12JJ4006)
关键词
压实土
蠕变
分数阶导数
本构模型
compacted clay
creep deformation
fractional order derivative
constitutive model