非饱和粉土的动模量和阻尼比研究

使用吸力可控或可测的非饱和土振动三轴试验仪，对非饱和及饱和粉土进行动力变形试验，在不同净围压应力、不同初始含水量的条件下，得到了非饱和及饱和粉土试样的动应力应变骨架曲线、动弹性模量和阻尼比，并量测试样吸力。试验结果表明：（1）非饱和粉土的骨架曲线比饱和粉土的要高；（2）在相同净围压条件下，不同含水量的非饱和粉土动弹性模量大小几乎相近，而饱和土试样的动弹性模量略小；（3）在相同净围压条件下，不同含水量的非饱和粉土阻尼比也几乎相近，而饱和土粉土的阻尼比略大。上述试验结果可以用现代非饱和土力学理论来解释。

Study on dynamic modulus and damping ratio of unsaturated silt

Dynamic deformation characteristics of both unsaturated and saturated silt have been studied, by using a dynamic triaxial testing apparatus for unsaturated soils, which can control or measure the specimen suction. Some test results have been obtained, including the skeleton curve, dynamic modulus, damping ratio of unsaturated and saturated specimens at different net confining pressures and water contents, and the specimen suctions were also measured. Test results show that: the skeleton curve of unsaturated silt is higher than that of saturated silt. Under the condition of the same net confining pressure, dynamic modulus and damping ratio of unsaturated silt are almost close for different water contents, while dynamic modulus of saturated silt is a little smaller than that at unsaturated state and damping ratio of saturated silt is a little bigger than that at unsaturated state. The above test results can be explained by the theory of unsaturated soil mechanics.