昆明呈贡重塑饱和红黏土的动变形特性试验

Experiment of dynamic deformation characteristics of remolded saturated red clay in Chenggong area of Kunming

为了得到不同试验条件下昆明呈贡地区的饱和红黏土的动变形特性演化规律,通过GDS动三轴试验系统,研究了围压、动载频率和固结比对重塑饱和红黏土动变形特性的影响.试验结果表明:随着围压和动载频率的增加,达到相同应变所需的动应力越大,动弹性模量也越大,阻尼比减小;随着固结比增加,达到相同应变所需的动应力越小,动弹性模量也越小,阻尼比增加.利用Hardin-Drnevich双曲线模型,对饱和红黏土的动本构关系进行拟合,拟合效果良好;给出了各试验条件下的拟合参数,并计算得到了最大动弹性模量和最大动剪切模量;两个模量随着围压和动载频率的增大而增大,随着固结比的增大而减小.

To obtain the dynamic deformation characteristics of saturated red clay under different test conditions,the GDS dynamic triaxial test system was used to investigated the saturated red clay in Chenggong area of Kunming,and the effects of confining pressure,frequency and consolidation ratio on the dynamic deformation characteristics of remolded saturated red clay were discussed.The test results show that with the increasings of confining pressure and dynamic load frequency,the dynamic stress for the same strain is required greater,and the dynamic elastic modulus is increased with decreased damping ratio.With the increasing of consolidation ratio,the dynamic stress for the same strain is required smaller,and the dynamic elastic modulus is decreased with increased damping ratio.Through Hardin-Drnevich hyperbolic model,the dynamic constitutive relation of saturated red clay is fitted with good fitting effect.The fitting parameters under various test conditions are given,and the maximum dynamic elastic modulus and the maximum dynamic shear modulus are calculated.The maximum dynamic elastic modulus and dynamic shear modulus are increased with the increasings of confining pressure and dynamic load frequency,and those are decreased with the increasing of consolidation ratio.