This paper presets the results of simple-shear rheological tests for the shallow clay layer in Shanghai and the rheological parameters of this clay layer

such as shear parameter

viscosity and long-term strength etc.

by using the obtained relationship among stress

strain and time. The test results show that with certain density and water content of the clay and shear stress less than the yield value

the relationship between shear stress and shear strain for the same shear duration can be obtained by superposition theorem. Because of its linearity

likewise

the relationship between long-term shear flow rate and shear stress also hold true thus

from the linear portion of the curves mentioned above the shear modulus G and viscosity η can be obtained . however

when shear stress is beyond a certain yield value

the curve becomes non-linear. This yield value can be regarded as long-term strength of the soil . In rheological experiments these parameters are all functions of time.