关键词: 营口软土, 剪切蠕变, 三轴蠕变试验, 蠕变模型

Abstract:

A creep test of marine deposit soft soil of Yingkou has been carried on the refitted triaxial shear creep apparatus. The relationship between shear strain and time of Yingkou soft soil is obtained under a series of different cell pressures and different deviator stresses. The analysis of the results show as follow: (1)The consolidated-undrained creep, which doesn’t include the volume strain, can be expressed by logarithmic functions as a type of   under a different deviator stress. (2)The shear creep behaves in a linear elastic character in a lower stress level, and it is a nonlinear behavior in a higher stress level. Therefore, a Singh-Mitchell experimental model and a generalized Kelvin model with five parameters are suggested, which can describe the shear creep character of Yingkou soft soil, and a method for model parameters determination is also put forward. It is found, fitted with data, that the Singh-Mitchell model has a higher precise in the stress level between 20% and 80%, and the deformation modulus and viscosity coefficient of Kelvin model all vary with stress level.

Key words: Yingkou soft soil, shearing creep, triaxial creep test, creep model