黄泛区粉土动力特性及动本构模型适用性研究

Study on the Dynamic Properties and Applicability of the Dynamic Constitutive Model of Silt in Yellow River Flood Area

黄泛区土质以粉土为主,对比黄泛区不同区域粉土动力特性差异,研究其动剪切模量和阻尼比的变化规律,探寻适合黄泛区粉土的动本构模型,可以为建筑基础、机器基础和土石坝的动力分析提供必要的依据.对开封、新乡和中牟三个区域粉土的动三轴实验,测得不同荷载下动剪应力、动剪应变以及应力-应变滞回曲线,并计算出动剪切模量及阻尼比.分析了三个区域粉土动力特性的差异,得出了固结围压、制样含水率对动剪切模量、阻尼比以及骨干曲线的影响规律,并通过Hardin-Drnevich等效线性模型拟合黄泛区粉土实测动本构数据,验证了实验数据的正确性和该模型对黄泛区粉土的适用性.

The soil quality of the Yellow River Flood area is dominated by silt soil.Comparing the dynamic characteristics of silt at different locations,the variation law of dynamic shear modulus and damping ratio was studied,and the dynamic constitutive model suitable for the silty soil in the Yellow River Flood area can be explored.The dynamic analysis of the machine foundation and earth-rock dam provided the necessary parameters.The test was taken from the silt in Kaifeng,Xinxiang and Zhongmu,and the dynamic shear stress,dynamic shear strain and stress-strain under different loads were measured by a series of dynamic triaxial tests on silt in different areas of the Yellow River Flood area.The hysteresis curve was calculated and the dynamic shear modulus and damping ratio were calculated.Based on the analysis of the data,the differences of dynamic characteristics of silt in different regions were compared.It is found that the dynamic characteristics of Xinxiang and Zhongmu silt are better than that of Kaifeng silt.The consolidation confining pressure and the sample moisture content were obtained.The effects of the amount,damping ratio and backbone curve were introduced,and the Hardin-Drnevich equivalent linear model was introduced to simulate and compare the dynamic constitutive model of silt.The model was applied to the silt in Kaifeng.