饱和粉质黏土动弹性模量影响因素分析及骨干曲线模型研究

Analysis of factors affecting dynamic modulus of elasticity of saturated silty clay and research on backbone curve model

为了研究交通动荷载作用下地基土动弹模量的变化规律,利用室内动三轴试验系统对东南沿海地区饱和粉质黏土进行动三轴试验,研究围压、超固结比、孔隙比和应变幅值对动弹性模量变化规律的影响;采用经典Hardin-Drmevich等效线性模型,提出考虑超固结比、孔隙比影响的饱和粉质黏土动弹性模量修正公式。研究结果表明:在相同应变水平下,动弹性模量随着围压和超固结比增大而增大,随着孔隙比增大而减小;与经典Hardin-Drmevich公式相比,本文提出的动弹性模量修正公式对试验结果的拟合效果更好。

In order to study the change rules of the dynamic modulus of soil under traffic load,cyclic triaxial tests were performed on typical Southeast coast soft clay.The influences of confining pressure,consolidation ratio and void ratio on the dynamic elastic modulus were studied.Based on the classic Hardin-Drmevich equivalent linear model,a modified Hardin-Drmevich formula of dynamic elastic modulus considering both void ratio and consolidation ratio was developed.The results show that in the same strain level,dynamic elastic modulus increases with the increase of confining pressure and over-consolidation ratio.When the void ratio increases,the dynamic elastic modulus decreases.Compared with the conventional Hardin-Drmevich formula,the proposed formula is more suitable for the fitting of experimental result.