关键词: 砂纹淤泥质土, 一维固结蠕变试验, 蠕变, 经验模型

Abstract: In this study, one-dimensional consolidation creep test was conducted to study the consolidation creep characteristics of the sandy grain muddy soil of Dongting Lake, and an empirical creep model suitable for describing the stress-strain-time relationship of the sandy grain muddy soil of Dongting Lake was established based on the test results. The results show that there is a good linear increasing relationship between axial strain ε and time t in double logarithmic coordinate system. In addition, with the increase of consolidation stress, the slope of - relationship curve decreases significantly, and the distance between - relationship curves becomes shorter under the action of two adjacent loads. Under high stress levels, the - relationship curve tends to be horizontal, and the decrease rate of the slope of the curve is significantly reduced. Moreover, hyperbolic function is more suitable than exponential function to describe the stress-strain relationship of the sandy grain muddy soil of Dongting Lake, and it is more in line with engineering practice to modify the strain-stress relationship in Singh-Mitchell model to hyperbolic relationship. It is found that the slope of the - relationship curve has a hyperbolic function relationship with the consolidation stress. On this basis, a modified Singh-Mitchell model with five parameters reflecting the influence of stress level and suitable for describing the creep characteristics of the sandy grain muddy soil of Dongting Lake is established.

Key words: the sandy grain muddy soil, one-dimensional consolidation creep test, creep, empirical model