湛江软黏土的流变本构模型研究

On rheological constitutive model for soft clay in Zhanjiang area

文章在湛江软黏土室内三轴剪切流变试验数据的基础上,研究了湛江软黏土的流变特性,通过分析蠕变曲线的规律,选择了广义Kelvin模型、西原模型及线性黏弹塑性模型描述湛江软黏土的流变特性,由非线性拟合结果得出七元件Kelvin模型拟合精度最高;结合不同围压下的蠕变变形特征及应力应变等时曲线几乎为直线的规律,得出了湛江软黏土的蠕变变形是以线性黏弹性变形为主要特征的;并建立了适合湛江地区软黏土的理论模型和经验模型,同时对模型的应用进行了探讨。

Based on the data of rheological tests on soft clay in Zhanjiang area under laboratory triaxial shear,the rheological properties of soft clay in Zhanjiang area are studied.Three styles of component models are chosen to describe the creep characteristics according to the analyses of the laws of creep curves,namely generalized Kelvin model,Nishihara model and linear visco-elastic-plastic model.A conclusion is drawn from the results of nonlinear simulations that generalized Ke1vin model with seven-components can describe the full creep procedures better than other ones.According to the rheological properties of soft clay under different compressive stresses and the fact that the stress-strain curve approximates to a straight line,it is concluded that the linear visco-elastic creep is the primary rheological property of soft clay in Zhanjiang area.Then a theoretic creep model and an experientia1 one for soft clay in Zhanjiang area are obtained,and the application of the models is also studied.